Vacation At Home.: You can turn off the phones, stop the mail, lock the doors, rent movies and dine in....or you can book a local hotel and act like a tourist in your own home town.
Go to other tourist websites to see what foreign tourists do in your town.
Visit your local chamber of commerce and pretend that you are a tourist and get them to recommend some things to do.
Find out areas that you have never been to. There are always places you've never been to or don't visit very often. Go there and walk around, there are most likely some things of interest for you to find.
Eat out, and try a new place you have never been to. Ask a stranger if they can recommend you a good place to eat.
When going out partying, act like you're not from town. You know it too, we all act different when we're in a new place. We're more open minded, care free and curious. You don't need to lie and say that you're not from there, but act like it and have some extra fun!