Sometimes a little self depreciation can endear you to an audience, but you should never have them laughing AT you... Unless you are the undisputed king of the schleps.
What a childhood I had, why, when I took my first step, my old man tripped me!
I tell ya when I was a kid, all I knew was rejection. My yo-yo, it never came back!
When I was a kid I got no respect. The time I was kidnapped, and the kidnappers sent my parents a note they said, "We want five thousand dollars or you'll see your kid again."
I asked my old man if I could go ice-skating on the lake. He told me, "Wait til it gets warmer."
Last week I told my psychiatrist, "I keep thinking about suicide." He told me from now on I have to pay in advance.
I tell you, with my doctor, I don't get no respect. I told him, "I've swallowed a bottle of sleeping pills." He told me to have a few drinks and get some rest.
My wife and I were happy for twenty years. Then we met.
I'm a bad lover. Once I caught a peeping tom booing me.
My wife only has sex with me for a purpose. Last night she used me to time an egg.
It's tough to stay married. My wife kisses the dog on the lips, yet she won't drink from my glass!
A hooker once told me she had a headache.
During sex my wife always wants to talk to me. Just the other night she called me from a hotel.
My marriage is on the rocks again. Yeah, my wife just broke up with her boyfriend.
The problem with being the "funny one" amongst your friends is that you have to be able to be at least slightly funny on demand. This is not as easy as you might think. The fastest way to get out of an awkward social moment is to drop a joke, the more awkward the moment the less funny the joke has to be.  But yuo cant go telling a dead baby joke to your boss and your friends at the pub probably wont like your office supply joke so now you have to memorize enough jokes to get you through any social setting.
Thats what I am here for. To talk you through the theory behind jokes and the basic structure of the joke so you may be able to craft your own joke to suit any situation.
This is called the "Thats what she said" Theory.