It is important to know the general layout of the parks before going in. This saves you time and frustration. I am not saying you have to know exactly but should have a good idea.
You can find them on the main Disneyworld website for each park. This will also tell you about height requirements and what those with disabilities will need to know (being able to transfer out of their wheelchair, etc.) It is important to know BEFORE you go to avoid disappointment and possible meltdowns.
Make sure to grab a new map when you enter the parks (great souvenir) but an easy way to be reminded where to go. Also, the Times guide is very helpful. You can also get this information on your My Disney experience App (which you REALLY want on your smartphone-hint, hint).