I needed a portefeuille (a billfold, or more literally, a leaf carrier or paper carrier) for my loyalty dollars from my favourite pharmacy so I knit one. It’s very easy, an idiot proof pattern for any beginner. You could sew it with fabric instead if you’re not a knitter.
Knit a rectangle wide enough to hold a $5 bill and or coupons. Make it long enough to fold both ends in towards the middle to hold your papers. Sew the edges shut, I did this with a crochet hook and a single crochet border. Leave a little space in the middle so you can fold the thing in half.
Mine is two different colours because that’s all the yarn I had. You of course would use one ball of yarn, or make up your own pattern.