Once you get to WDW and your resort, you will be amazed at how easy it is to get around.
Basically, the buses run every 20 mins...at the busy times of day (park opening and closing) they run more frequently. There is very good signage at the parks so you will know exactly where to go...same with the resorts.
Buses start running, between resorts and parks, about 6:30am. BUT..they do not run every 20 mins....there could be a longer interval between buses. They are primarily for those with early morning ADRs and tours within the parks.
Boats start running about an hour before park opening. Monorails start around 7am.