First of all, find a cardboard box that's the right size for all of your stuff.
Place it in the drawer where you want to keep it and roughly cut it to size with a box cutter - making sure that it will fit nicely.
Neaten up the edges.
Cut a large square of lining fabric and then place inside the box, using a glue gun to stick it in place.
Cut a really long strip of fabric and glue around the outside edge of the box. I folded it over at the top, so that it would have a nice clean edge - kind of like sewing, but with glue instead.
Turn the box over, so that the bottom is facing up.
Fold the fabric like you would if you were wrapping a present and glue down.
Flip back over and you're box is all finished.
Pop in your underwear, or whatever you want to keep in it.
You can use my new <a href="http://www.cutoutandkeep.net/projects/fold_underwear/">how-to</a> to learn how to fold your underwear in to neat little squares.
Pop the box in your drawer and rejoice about how organized everything is.