fabric softener solution and dry it again.
put your jeans on. slip on the loose pair of jeans, zippering and buttoning them up as usual.
this is the only method in which you must wear your jeans as you shrink them.
since you will be shrinking your jeans as you wear them, the jeans will shrink around your legs, create a perfect, snug fit.
you should begin this process on the same day you plan to wear your jeans. if this is not possible, then use this method to shrink your jeans a day or two before you wear them. do not wash the jeans after shrinking them, though, since doing so could cause 