1) Just wear them to stretch out the waist. If you don't want to do that, you can cold soak it inside out for like 30-45 minutes (I used woolite dark) and then stretch the waist with your hands and then hang dry which is what I did. I wore it the next day after it was dry. Some people wear it when it's damp. It's up to you. 2) If you cold soak it, hopefully it got rid of any potential shrinkage and then you can get hem hemmed. How much is up to you and how big you want the cuff. 3) Can't help you there. I like button flys.