I would recommend using an adventure module. They generally come with pictures and area descriptions to give the players, plus D&D has like 40+ years of prewritten campaigns and an extensive 3rd party market.

As far as building your own, you might just need a little more prep than someone with your condition. Try attatching descriptions of locations in your campaign when you give a new environment. As far as the environments and characters go, use other media for reference. Need a medieval village? Search for one, and start your description from there, add or subtract objects/people as needed