I don't have an answer for pre-washing but I do have some advice for post-washing. DON'T DO IT IN YOUR WASHING MACHINE. Take it to the laundromat and do it there. Dry it there also. You might even do it a couple times while your there. lol They fray ALOT and there is NO WAY I would wash one in MY washer nor would I dry it in MY dryer. lol Pay the couple of bucks and save yourself come repair bills.