Bounties = if you want to participate you can see many different bounties in altcoin bounties section
This is helpful for you to improve your posting in this forum. By joining bounties, this will urge you to make quality posts, read a lot of information as your source, and it can widen your understand and knowledge. If you participate in bounties, you will understand more the importance of the subject that you are focusing on your bounties.
Services = if you have skill to offer in a project and they need it they will pay you a token or btc for that service you provided.
Some of the projects here in this forum really pay you depends on your skill and on how fast you do a certain project. If you think that you are qualified for this, don't hesitate to join and help those people who are managing a project. Just provide the service that they need with effort, hard-work and passion.