When you finalize the development of an Issue and you want to be available for Validators to confirm your work and propose a distribution of the bounty, you should "Create a Pull Request" via the webapp.

After this, the issue creator can analyze your solution and "Recognize as Finished".

After that, you will be able to see if any validator proposes a distribution. If you win, the distribution should be done and you should receive rewards based on the solution.