There are a couple of ways to interpret today's prompt. When you illustrate something, it could mean a couple of things. According to google, here are the definitions.

1. provide (a book, newspaper, etc.) with pictures.
2. explain or make (something) clear by using examples, charts, pictures, etc.

Since I am not an artist, I illustrated this prompt using some items I found in my yard. I think it illustrates to you someone going for a walk.

If you are artistic, feel free to draw or paint something for us!