If you are really interested to sell service and get clients from this community then my suggestion will be to buy copper membership which will enable you to post image. But that's not all.
Once you will have the copper membership then on the service announcement board create a nice topic which will serve as a homepage for your service. The topic has to be graphically reach, just like a nice website. Your service details, contact details everything should be on the same page. Nurse the page, keep it updated regularly, engage with potential clients and build a network.
And the best practice will be to become active in the community. Active does not mean you replay and post in every topic. Don't spam but get to know with the community. Share you knowledge, do not be so selfish. Share whatever you know and help others to improve their knowledge. Also ask for something that you do not know. Know which board works for what kind of topics. Build a community around you. If you are a crypto lover then you will love this place. Hope the free tips helps.