How to make a shopping cart cover for baby?

So I purchased a shopping cart cover for my baby and i love it. I have to friends baby showers that are coming up and I want to make them both one instead of buying them because they are very pricey. Does any one know how to make these or have made them before? I have an idea but i rather have a better idea of what i am doing. If any one can help that be greaT. THANK YOU

Try this site:

http://www.shoppingcartcoverpattern.com/