You can take Sand Lake Road West until it pretty much dead ends at Apopka-Vineland Road. (It doesn't actually dead end, but if you kept going you would be in a subdivision). Anyway, at Apopka-Vineland you would make a left turn and head south. You would be on this road for a few miles and then would actually be approaching the Crossroads and the Entrance to Downtown Disney from the North. You will see the big signs for Walt Disney World at Hotel Plaza Blvd. You would be making a right here on Hotel Plaza Blvd. From there you could follow the signs to where ever you wanted to go in WDW. There is a different 'back door' entrance but it is pretty confusing and I don't recall the street names. Anyway, you may want to consider taking Apopka-Vineland road if you plan on going to or from WDW during rush hour. I-4 can be a mess at those times.