Nearly everyone has been in a position where they left their keys locked inside the house and have tried to figure out a way to get back in quickly. While you could always call a locksmith or other professional, you might not be in a position where you have access to a phone or have the time or money to wait around and then pay a locksmith. If you have access to certain lock-picking tools, you can very simply manipulate the lock without damaging it to regain entry to your home.
Place the shorter end of a tension wrench in the bottom of the lock and a fraction of an inch inward. Turn the tension wrench in the direction that you rotate your house key when it is in the lock. The tension wrench won't be able make a full turn, but will only turn slightly in a given direction, which is fine.
Slip your metal pick into the top of the keyhole. Slide the pick in and out of the lock at different speeds. Your objective is to push all the pins inside the lock upward so that the door unlocks. Sometimes you will want to do this slowly and firmly, while at other times you should try jiggling it vigorously. Be very patient with this step, as it can take several minutes. Hold your tension wrench in place as you do this. At some point you will hear a click and feel the lock give slightly.
Turn your tension wrench in the direction that you've been holding it. The lock will turn completely, and you will be able to open the door to your house.
Never pick the lock to someone else's home, as it is illegal. Carry identification with you in case you're questioned by a police officer and need to show proof that the home whose lock you are picking is your residence.