[DOs] DO set up a dedicated email address: as it will mean you can more easily track your survey activity and your normal email won’t get inundated. [DON'Ts] 
DON'T expect to qualify for each survey: every survey is designed for different demographics - some need opinions from parents, some from students and some from pensioners. Don't get upset if you get screened out from the survey, next one might work well for you!