And paste the hashes they are looking for, click search.
Those sites are connected to huge databases with billions of cracked hashes, if the person posting the thread haven't used them before posting, you will get hits.
From experience i can tell you that most of the time they don't use those sites.
Most of the time it's easy 5-10$ per thread, sometimes you can stumble upon a thread you will make 50$~ from.
You won't make crazy money from this, but when i used to do it for 3 weeks i managed to get 450$.
The advantage is that this method requires close to zero effort, so you can combine it with a few others and make few grands per month.
Good luck!
RE: (In My Opinion) The easiest way to make money on forums