Do NOT
insert links (not even in profile information) to anything to do with anything illegal or heavily borderline so. (Use your judgement or someone else will...) In general, signatures to guns, adult, erotic, "hardcore dating", escort, scams, fraud, piracy (including software, movies, music etc. + including torrent and similar file-sharing), casino/gambling (including roulette, slot machines, poker etc.) and similar will be deleted on sight even if it is not illegal in your jurisdiction.
Do NOT
insert links using URL shortening - i.e. so the true URL destination link is hidden
Do NOT
insert extra links in bottom of your posts. You have a signature profile setting for that.
Do NOT
make repeated one liner posts where you happen to link drop the same URL again and again and...
Do NOT
have majority (...) of your posts consist of "fantastic post", "inspiring post" or "thank you" short comments.
Do NOT
copy (and spin) someone else's post and post it yourself...
Do NOT
Copy (and spin) someone else's writing (from another website) and post it yourself... If it reads like nonsense spun text, it will get deleted.
Do NOT
E.g. posting one-liners in official product support forum boards suggesting competing products. (Much more leeway is given in general boards where you can recommend your own or other competing solutions assuming someone asked for such suggestions. But for threads in official support forums - you can not just post short one-liners recommending and/or linking competing products)