DO keep ground floor windows and doors securely locked whenever you leave the room. Wallets, laptops, handbags etc. can be stolen by sneak thieves..
DO close curtains in the evening and at night so that passers-by cannot see you.
DO be careful when answering the door. Don’t allow anyone in unless you are sure who they are. It is a good idea to fit a chain to your front door or to call out to ask who is there. Ask to see identification.