This week I made a baby wipe case for a friend's baby shower.
I found fabric and some batting about 1/4 inch thick. Both were 1/4 of a yard. I found a wipe case at Target for a dollar. I recommend finding a case that closes really well. I could have used one that was better, you don't want it to open in your purse.
I first cut the batting stuff larger than the case. I hot glued the batting on and around the edges. I then cut the access off. I did it for the top and bottom.