Helper, that didn't... Well... Help

I think his question was HOW, not HOW OFTEN
Assuming this isn't some trollish account, I shall explain the simple task of "Bumping".
Occasionally, a thread will not get a lot of answers. Maybe people don't know. Maybe they're watching the top list of the busy threads, and yours got knocked down by new posts in other threads while they were typing something, or looking away. Ya never know WHY, but the point is your message does not receive the answer/reply you want.
So, you "bump" it.
How?
Simple.
A bump is really just a reply to your own thread. You simply type "Bump." and maybe a reason as to WHY you're bumping your thread. With the new reply, your thread is back at the top of the busy thread-list, and as such, it's easier for people to read it
That, my friends, is a bump. All it is is a reply telling people that the answer hasn't come yet.
Please remember there ARE a few (really only 1 or 2) rules to bumping.
Like what TH said: Only one bump in the same thread for 24 hours. And you should really only bump a thread if it's being pushed onto page 2.
Ta da. The art and the way of the bump.
Fear it. Always.