I have an question i want know is bumping legaly?
If yest how to bump with out warning

It depends on the thread.
But when you bump something, always ADD something to the thread. Don't just make a crappy post that just says 'bump' just to bump your thread.

Basically for the market:

Bumping after 24 hours is allowed, if you add something relevant like another item, or change something like an autobuy.

For other boards:

If you can post or bring up something that still has relevance to the topic and hasn't been stated already, then post.

Something you wouldn't want to do is use another alternate account to bump your threads, asking questions or prices.

Ok thanks now i know
Fee's post wos the best