The basic table is the only "default" feature of RTDs, and even that gets altered sometimes. Accordingly, there's not a whole lot to learn on the ground floor.
So that leaves most of the advice I can give you as things to make your game healthier. A few of the major ones include:
1. Simplicity. As with D&D, everything you do needs to be done by hand, which means it starts to add up fast when parts of your game are kind of complicated. Since most people's tendency is to keep coming up with new and more complex systems to add to their game, the usual advice is to keep it as simple as possible while still doing what you want it to do.
2. Motivation. Forum games are very dependent on the GM, which means the GM being motivated is vital to game health. Accordingly, you should make sure whatever you're running is something you find genuinely interesting and enjoyable, to maximize the chances that you'll feel like running it for a long while.
3. Failure. Forum games are not usually terribly complicated affairs, so it's alright when they peter out or never get off the ground. It's not ideal, of course, but it's better to fail and learn than to never try or be too conservative about it. You don't want to consciously make mistakes, but you don't want to worry too much about making the perfect game.
There's infinite other advice we could give, but most of that's subjective or situational. We do have a
discussion thread for RTDs, if you want general advice or to run a concept or system past some people.