If you are doing cash in hand work while claiming job seekers how can you disguise yourself ?

if you are mowing lawns etc for cash in hand but claiming job seekers to prevent a job centre staff member driving past and seeing you is it wise to always wear a hat and sunglasses and overalls while working. Also if you are working but living with other people is it wise to not tell anyone you are claiming and keep quiet to EVERYONE about any work you no matter how small it is? Super secretive?