Ok, the tension wrench is used for turning the plug (circle keyhole bit).
You need to push the pins in the lock up.
If you don't turn the plug (keyhole) the pins will just
fall down.
If you keep SLIGHT pressure on it, the pins will stay where you left them.
You need to get yourself to the FAQs section and have a good read around in the newbie section,
especially the thread called,
"READ HERE BEFORE POSTING"
or something along those lines.
Do a Google search for MIT Guide to lockpicking,
have a few reads of that, which will explain exactly
HOW to pick a lock.
This is a great link too, for visualising and understanding what is going on in a lock:
http://deviating.net/lockpicking/topics.html
I would probably not post anything else until you
have had a good look around and used the search function.
We answer a lot of the same questions every day, so
I doubt that there isn't a thread on what the next 200 things that you will be wanting to know.
Enjoy the site