The non-sleazy way to sell on forums

Nice way to describe the feeling of try to sell in forums. I've heard the advice time and time again but most articles just talk about the task at a macro level rather than suggesting a step by step, build it up slowly approach.

I think much of the fear of taking it slowly is perhaps realising after 2 months that the 2 forums/groups you chose are the wrong ones and that you have to start over somewhere else.