Some years ago I made a wallet that I loved, but did not fully instructablize it. It wore out; I made another just like it: here's how!

You need only about half a square foot of fabric. It needs to be reasonably stiff; denim or heavy cotton is ideal, and you may have suitable scraps in your scrap pile. You also need a couple yards of thin double fold bias tape in a matching color (or anyway a color you like). Thread, scissors, tape measure, sewing machine are the only other requirements.

Step 1: Cutting and Edges

The wallet uses only three pieces of fabric, the outer piece, and two inner pieces forming the inside of the money pocket and the card pockets. The dimensions I used are these:

8" x 4"
7 3/4" x 3 3/4"
7 1/2" x 3"

I worked out the sizes from laying out 3 credit cards in the arrangement I wanted, with a suitable amount of space in between, and accounting for about 1/8" edging around all sides. The significant idea is that each piece is a quarter inch shorter, lengthwise, than the next biggest. The ends, however, will be sewn matching up, making the outside long and the inside short. Properly controlled, this length differential creates the desire to fold up which is this wallet's most excellent feature.

Sew bias tape to one of the long edges on each of the two smaller pieces.

Step 2: Sewing the Folds

Lay the pieces out with the largest face down and the two smaller face up on top. Align one set of edges and pin. Fold the pieces together in a trifold as the wallet will eventually be carried, and work the pieces so that the unpinned ends match up, and each fold in between has approximately the same amount of looseness at each layer. This is easier to see in the pictures than to explain. When it sits right, pin at the ends and on either side of each fold.

Sew from one end up to the first fold, skip the folded bit between the pins, sew the middle section, skip the second fold, and sew to the end. The skips are to allow the areas that should match up to match before attempting the more difficult sewing of the unequal lengths, which we will do next.

Step 3: Pockets

I did this out of order, but now is a good time to sew the pocket lines so that cards in each section of the trifold can't slide to the other sections. You want to find a sewing line that's as close to the middle of the uneven-ness of the folds as you can, but it isn't too vital if you get it a little wrong. You should have plenty of ease for a number of cards if you used my measurements; if you made your own, hopefully you read ahead to here and allowed some room for folding!

The seams don't have to run all the way to the bottom, as long as they go more than halfway from the top, bound edge, they'll be fine.

Step 4: Finishing

The final step is to bind the wallet edges. I erred here and made my binding join on the end I wanted to go on the outside... you might want to put it on the inside end, or at a corner. It doesn't matter except visually, as long as you don't try to join over the unequal fold areas, which would make that sewing even harder.

Start applying the bias tape, again wherever you like, and just go all the way around. When you get to the unequal folds, put some effort into easing the longer edges in, sometimes putting in a lot of pins helps with this. You can sew those down before the bias tape if you like. You may end up with a tiny pleat or two but if you've managed to get the pleats fairly centered on the fold lines, it won't affect the wallet and it won't even really show.

That's it. The wallet is complete and ready for use. It will only want to fold up at the bottom seam at first, but if you iron it, or just carry it in a pocket for a day, the rest of the folds will settle in and it will stay nice and flat.