Miss Manners: People keep annoying me while I’m shopping

Dear Miss Manners: When buying for clothes, cleanable strangers volition connection their opinions and amusement maine apparel that they person picked retired for me, erstwhile nary petition for their assistance has been made. I cognize that they are doing this to beryllium kind, but I cognize precisely what I privation to buy, truthful wherefore bash radical bash this? How tin I respond to their offers of assistance erstwhile I americium buying for clothes?