matt's go-to method for washing his jeans. he'll even tub soak before he starts wearing a new pair. if you've got a bit of time (and don't mind cleaning your tub out after) the tub soak is a great way to wash your jeans.
1) fill your tub with lukewarm bath water, add in a bit of detergent
2) submerge the jean and gently agitate the water, moving the jeans around, wipe away any excess dirt
3) let the jean soak for 10 - 15 minutes
4) let the water drain from the tub, and while draining, wring out any excess water from your jeans
5) hang the jeans to dry, make sure to smooth out any wrinkles or creases in the fabrics