This information is from my famously infamous "How to
ECV at WDW" post, and I'm only going to copy and paste the part about buses here.
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Mostly it's all about the buses (and boats, and Monorail and Skyliners too, for that matter.)
When we talk about using the "brakes" on an ECV, what we really mean is letting go of the throttle. The vast majority of
ECVs in the US don't have an actual braking system (like a car or truck has) and rely strictly on the driver of the ECV to be aware, and to let go of the throttle when they need to stop. Additionally, most ECVs that you will encounter have a speed control that goes from slowest to fastest, with a small icon of a turtle for slowest, and a rabbit for fastest. We often talk about "turtle speed" here, and that means turning your speed control all the way down to the slowest setting for safety.
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Let's get on the bus!
Sometimes people worry that other Guests are watching them when they use the ramp to drive their device into/out of the bus. I've been using a personal mobility device for *years* at WDW now, and I know that people who appear to be staring at you when you are loading/unloading from the bus really are often just watching out of curiosity.
Think about it like this: The bus pulls up, and everyone gets off. BUT before anyone can get on, the driver closes the front doors, and the back doors, and then walks to the back of the bus. The back doors open again - but only *after* the bus has "kneeled" (with a great huge wheezy gasp) and then barfed out a ramp with all kinds of beeping as well!
It's a wonder that Disney hasn't decided to sell tickets for the spectacular that is the bus deploying/retracting the ramp!
So, often the folks who may (to us) appear to be staring at us, are actually WDW newbies who are startled by all of the commotion. But it's the *bus* they are watching - not the scooter driver.
And some of them are just flat out exhausted, and staring off into space, unaware that they are looking at anything at all!
So, ignore them - and at the Resort Hotel, make sure you are parked in the white painted rectangle HA symbol

at the bus stop (unless another guest beat you to it) so that the driver sees you, and knows you are waiting to ride. As the bus approaches, I usually try to wave and smile to let the driver know I will be riding their bus, or shake my head "no" so that they know I am waiting for a different bus. Some Disney Resorts have queues or rope lines set up for the buses; others just kind of form loose lines. Often in the mornings, there will be a CM at the main Resort bus stops; just as at the Parks, take your guidance from them. (Special note for Resorts with more than 1 bus stop: Try to make your way to the *first* stop at the Resort; as the bus travels through the Resort to pick up other Guests, the chances increase exponentially that there will not be a space for your ECV when the bus arrives, leading to longer wait times.)
Once the bus stops, and everyone is off, the driver will typically close the doors, kneel the bus (lower it), and then open the back doors and flip out the ramp. Wait for the driver to motion you on, and then up the ramp you will go.
When the driver says that it's time to board the bus, just let them know that you are a newbie, and will appreciate all the help and guidance that they can give you. Remember - they are an *expert* at getting folks on and off the bus, so just take a deep breath, and listen to their instructions, and everything will be fine! Disney bus drivers help *thousands* of people load and unload ECVs, so you are not a surprise to them in any way!
When you are at the base of the ramp, try to go right up the center. At the top of the ramp you will typically have to turn a bit to the right. GO SLOWLY, especially until you are used to the ECV. (This is a moment where "turtle speed" is your new best friend!) Even experienced users take this carefully - the last thing you want is to bump into the driver, or hit the side of the doorway going in. The drivers will give you instructions and will help as much as they can, but *technically* it is up to you (or a member of your party) to actually get the ECV up into (or back out of) the bus. You will hear stories about drivers that "park the ECV for you", but that is considered "pixie dust" and is not expected behavior.
Once you are parked, you can take a seat on the bus, if you want to. The bus driver will "tie down" the ECV, by clipping on the tensioned belts down at the wheel level, front and back. If you decide to sit on the ECV during transit, the driver will also offer you a seat belt to help hold you securely in place as the bus moves through traffic.
With buses, you will typically board first, and disembark last. Ignore anyone who says anything about how "it must be nice to get on the bus first"; if you really feel the need to reply, just give them your biggest smile, and a big 'ol southern
"Oh, bless your heart!". That's all they deserve.
If you are just too worried about driving on and off the bus, someone who is with you can do that for you. Again, they just have to follow the bus driver's instructions. You can walk up or down the ramp after the driver tells you it is safe to do so.
While you are boarding the bus, the rest of your group will wait outside the bus, next to the ramp. Once the ECV is parked on the bus, the driver will indicate to your party when they can walk up the ramp to join you, and they should be able to sit near/next to you.
When it's time to disembark from the bus, the rest of your party can get off the bus with all of the other passengers, and they will wait for you outside the bus (or wherever you have agreed upon). Again, the driver will assist you in getting the ECV positioned to drive down the ramp, and out of the bus; listen to their instructions, and you should be fine.

When driving off the bus, the most important thing is to make sure that you don't turn your front wheels (or the "tiller" - the steering mechanism) until AFTER your rear wheels are completely on the ground,
and you are completely clear of the ramp. You don't want the rear wheels to catch the edge of the ramp if you turn too early, and tip you over!
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As far as boats go, *most* boats at WDW are quite accessible; the notable exceptions are some of the small launches that serve Poly/GF to MK and back, and a small launch that runs every other trip on the WL/MK route. At WL, the bigger boats historically don't use a ramp there, and you just have to hope that the water level (and number of people on the boat) work in your favor! (Makes it kind of exciting LOL!) We have had a CM instruct us to wait while more people board/disembark to lower the boat, and then when the doorway is at the optimum height to the dock, they wave us on. (Pro tip: DON'T LOOK DOWN as you pass over the gap

) All other boats will have a portable ramp that a CM (Cast Member) will place for you, including the Sassagoula fleet that serves Saratoga & The Treehouses/OKW/POR & POFQ, and the Disney Springs Water Taxis (which are the same type of boat, but have not returned to service since pandemic closings.) The Friendships that ply the waters between Hollywood Studios and the International Gateway at EPCOT use the exact same ramp as well. The ramps are *noisy* when driving on and off, but quite safe, I promise! The main thing to watch for here is using "turtle speed" coming *off* the boat - if there is no fencing around the dock, you don't want to make a BIG "splash" in more ways than one!
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The Monorails use the same portable ramp for loading/unloading as the boats use, and the worst part is some of the pedestrian ramps going *up* to the Monorail stations may really tax the battery on the ECV. A CM will place the portable ramp into the Monorail for you - just follow their instructions. Most of the time, you will have to back off down the ramp at the next station. Remember to keep your wheels straight, have someone behind you giving you clear verbal cues, (CMs are used to doing this, and will be glad to help you) and take your time for safety.
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The Skyliners are VERY accessible, and the gondola cabins are a direct drive on, no ramp needed. CMs will "chock" the ECV wheels to prevent it from rolling across the cabin while in flight. The user simply rolls straight in and sits between the benches. Follow the signs and CM directions at each Skyliner station to go to the HA loading area - they fully stop the gondolas to load there, and you can take all the time you need for both loading and unloading. The exception is Riviera - they cannot stop the Skyliner there, and so loading/unloading is only done while moving. There is not a pull-off loading/unloading area at Riviera that other Skyliner stations have, but the Skyliner cars slow to a crawl while going through the Riviera station - so if you feel like you can drive on board, or back off the Skyliner while it is moving, Riviera is no problem.
Only 1 ECV (or personal mobility device of any kind) per Skyliner Cabin, so be prepared to split up here if you have a larger party, or more than one mobility device in your group; just make plans for where everyone will meet!
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In general: Whenever loading/unloading from Disney transportation of any kind, use the *slowest* possible speed on the throttle control, and listen to the CMs who are there for your safety. They are all experienced in helping Guests with their mobility devices.
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There's a lot more info (this is, after all, the Reader's Digest Condensed Version!) but I just want you to know that it's not super hard to drive on the bus, and you do have options. I promise - if I can learn to do it, anyone can!