It is worth keeping in mind that branching narratives can get out of hand a lot more easily than linear stories, so being aware of the scope of what you're writing can be extra useful. Also, don't be afraid to cut down on things if the story starts becoming unwieldy. Planning things out might be helpful.
However, I don't really want to tell you how to write, because there are many ways that work, and you just want to find what's best for you. With that said, if you haven't written much before, don't be afraid to experiment and try different things.
How to Write
Other than that, dialogue punctuation is something many people get wrong, so brushing up on it is a good idea (even if you think you do it right, because the rules aren't the most obvious thing). Here is a site article on it: Dialogue Punctuation.
Actually, there are a few articles under the Help & Info section which deal with the actual writing, so looking through them might be beneficial.
Asking for feedback on writing in the Writing Workshop or Creative Corner is a good idea as well (they're for different things, depends on what you're posting).
Reading
Another piece of general advice is to read. Reading stories on the site is a good way to get a feel for the expected quality. Reading linear books by professionals is also good, and pay attention to the writing when you do, as most published books have editors (I assume) so they are punctuated and written correctly. Or don't pay attention, learning through osmosis should still work!
Site
Main things regarding the site are that:
- Stories split into parts are generally frowned upon, demos especially so, so know that publishing is for finished works! Sneak preview can let people see unfinished works. (Though do note multi-part stories can exist, however each part should be capable of standing on its own).
- This ties in with the previous point, but some writing sites encourage users to publish piece by piece (i.e. chapter by chapter). That is not the case here.
- This may be 'just a forum', but taking care to capitlise your i's and names is worth doing, because it is a writing forum (you're good on this front though).
Also, consider backing up your work, as it is good practice. (I think it might have gotten fixed, but the editor was capable of timing out, which means work could be lost. You could mostly avoid this by saving to clipboard [copying] whatever you had written before hitting save).
Conclusion
I'll stop there because I think I mentioned enough things. Other people can fill in any gaps for things I missed. If there is anything that isn't clear just ask and I should be able to explain it better.
Other than that, welcome!
