Hi raymondcky,
I've done the Shark Dive 3 times now so I hope I can help you out.
Roughly I'd say plan for this to take around 2- 2 1/2 hours from your day.
When you enter the park we needed to confirm at the information desk that we were present for the dive, they marked on the map for us were we needed to gather.
Once there we was greeted by a cast member you will be taken behind scenes to a classroom type of area where you will be told about the sharks and other fish in the exhibit and can ask any questions, an explanation of the helmets they use (i'll say more about them in a bit) and safety tips ie no poking your fingers through the bars of the cage.
After this you'll be taken into a building where you'll be given a wet suit, gloves and water shoes (You will need to bring a swimsuit with you as well). There are lockers in the changing room area to put your belongings.
Then you'll head over to Shark Encounter and will go up to the top of the medical pool (a waist deep pool on the edge of the main tank). There will be a couple more cast members here and they will aid you with putting on the helmets (they are very heavy out of the water.) Before stepping into the cage which is lined up with a gate at the pool edge.
The helmets themselves constantly pump air into them and that in turn keeps the water out. There is a microphone build into the helmet so you can ask questions to the cast members and they can check that you're comfortable.
Once your inside the cage will move slowly across the tank before returning to the start point. Inside the cage there is a large plexiglass window (sometimes it is hard to see from inside the veiwing area) and a few handle bars to hold on to.
After the dive you'll be given a bottle of water and taken back to the changing area, there are showers here as well. After changing you'll be given a bag containing a T-shirt and a Booklet about sharks and taken back to the gather point in the main park. During your dive a there will be a photographer taking pictures these can be veiwed at the information desk where you checked in earlier.
If you have people viewing your dive, they can watch from the tunnel area, however my family have been allowed to watch from the Sharks grill, (although my dives where before the grill's opening time, so not sure if they allow this during serving hours.)
~ Claire