This is what the police Website recommends:
Remember, always lock before you leave
Last year, 5,199 people were burgled because they didn't lock their front door. It's easy to leave your front door unlocked, especially when you're in a hurry or distracted. But even if you only do it once, that could be enough to get burgled. Most burglars are opportunistic - they look for an easy way to get in that won't take long or arouse suspicion, so many try the front door first.

How does a burglar's mind work?
Burglary, on the whole, is an opportunist crime. A burglar will select his target because it offers him the best opportunity to carry out his crime undetected and with the fewest number of obstacles in his way. A building that presents itself as unoccupied and insecure is far more likely to be targeted than one which is properly secured:

Side gates open
Accessible windows open
Ladders left out, allowing access to otherwise inaccessible windows
Garden tools available to force entry
Untrimmed hedges or high fences preventing natural surveillance
Each of these makes access to the building far simpler and is an indication to the prospective burglar that it's worth a second look.

Residents of multi occupancy dwellings or flats should be mindful not to grant entry to people via an entry phone system, if they do not know them, and to be cautious of people seeking to 'tailgate' them into buildings.


The question is, are the occupants in?
Milk bottles or parcels on the doorstep
Newspapers and mail in the letter box
Unlit houses after dark
All windows shut in very hot weather
These are signs telling the burglar that he is unlikely to be disturbed in the course of his work. Naturally, circumstances may arise when such situations may be unavoidable. If we can take measures that tell the burglar that this building is too difficult or too risky a target, he will hopefully move on.

TO STOP A BURGLAR,
YOU NEED TO THINK LIKE ONE.
To a burglar, a stuffed letter box is a dead giveaway when you’re not at home. Ask a neighbour to remove your post while you are away.
Are you leaving a thief the key to your house?
Never leave a spare key concealed anywhere near the front door - burglars know all the hiding places
Prevent letterbox burglaries by storing keys away from the front door
Do not label your house keys in case you lose them and they fall into the wrong hands.
Remove temptation
Where possible, try to keep valuables out of sight from windows.

Make it look as though your house is occupied
Install timers which switch lights or radios on and off automatically.
Have a neighbour or friend pop round to clear your letter box or doorstep.
Encourage a neighbour to park on your drive.
If going out after dark, draw the curtains, leave some lights on and a radio playing.
TO STOP A BURGLAR,
YOU NEED TO THINK LIKE ONE.
To a burglar, a dark doorway is an opportunity to hide. Fit a security light over your front door to deter burglars.
If you are away for extended periods.
Cancel the delivery of milk and newspapers
Disconnect the telephone answering machine, or re-word your greeting message to give the impression that you are only temporarily unable to answer.
Enlist the help of a neighbour, friend or relative to keep a regular eye on your property and keep the front door clear of deliveries.
If you are prepared to leave a key with a willing neighbour/relative, ask for curtains to be drawn and lights to be put on at night. If snow is on the ground a few footprints will make the house appear inhabited.
Check your insurance policy. Some insurance policies for contents don't cover you if you are away for more than 30 days.
Set your burglar alarm.
If you do not have an alarm, consider investing a few pounds in a dummy alarm box. It may well deter the opportunist thief.
Remember: Remove the Opportunity - Prevent the Burglary

TO STOP A BURGLAR,
YOU NEED TO THINK LIKE ONE.
To a burglar, a dark house is an empty house. Attaching a timer to a lamp will make your home appear occupied even when it isn’t.