As a general rule, I don't pre-wash, I like the old fashioned crinkly looks. Any fabric I plan on cutting, I starch at least 2 hours before I plan on using, then I either air dry, which I prefer or put in the drier for a few minutes, then iron. I also use the concentrated starch, Sta-Flo and mix 50/50. I've never had a problem with bugs, but I think that if you have no problem with bugs prior to starching, you won't have a problem with them afterward, but this is my honest opinion not a fact.