and welcome to the DIS!! I believe anyone can do this not just DISers. I'm going to shamelessly advertise my 10th anniversary as well as the fact that I'm a DISer. Some people use lights, pics of fav. characters, streamers, posters, you name it. If it will fit in a window or on a door - you can do it!!! Check out your local 'dollar store' or Walmart for cheaper Disney items and get creative. There is a DIScreative board here with all kinds of great ideas from clothes to Mousekeeping envelopes. Check it out.
LOL! Go for it and Happy Anniversary!

By the way, I'm from the Caribbean so no Walmart here. Don't I wish!!