I like the washing first and throwing into the dryer to see what it looks like after that. I am leary about the stretching to fit process if it is going to be washed again after using it as most likely the fabric will somewhat go back to how it wants to be. However, sometimes quilting it does help it stay put. Anyway, it will be a challenge. Good Luck. I really have trimmed a panel so that it lays square if I can add other borders to make it look OK.