I was not willing to purchase an expensive minky contoured changing pad cover (like this one), so I made my own with minky remnants that I had leftover from my crib bumpers. Most people that make their own cover put elastic in the bottom, but I found out that it's not necessary. The corners are sewn in such a way that keeps everything nice and secured.
I followed this tutorial from the Cozy Pumpkin and I think it turned out great!
Total cost to me: $0. Score!