It's good to ask the Post Office to hold your mail Put your newspaper on hold if you get one. Cancel your milk delivery. Anything else that you need to cancel?
When we're gone, we ask someone trustworthy to check the outside every day and to water the flower beds. We give a key so packages left at the door may be placed inside. If we're gone for quite a while, we often hire someone (usually a neighboring teenager) to cut the grass for us, front and back, and weed the flower beds. The idea is to make the house look as "regular" and as lived in as possible.
We let the closest neighbors know we'll be gone, particularly the neighbors who can see our front door. If they look out and see someone at our door or in the yard, they'll know there might be a problem.
I like to use two or three light timers (inexpensive, basic ones) so it really looks as if people are home. Set the different lights to your normal schedule. If lights go on and off in various parts of the house, it might keep the burglars guessing.
You could even ask neighbors if they wouldn't mind parking in your driveway at night.
Jill is right in suggesting you remove any obviously enticing objects. Entertainment devices, televisions, laptops come first to mind - along with any antiques you might have. If you have valuable jewelry, put it in the bank, the laundry room, or the fridge (in the back). Think like a thief: what would interest you? If you saw one thing you'd like, what else would you think to look for?
Make sure someone knows how to contact you if the need should arise.