Please post info how to not build links

All I see everywhere is how to find places to build links and what software to use.
I can't find any information on how to avoid doing things wrong.
I think most of us here would appreciate if people could share their don'ts .

My don'ts are a currently only a few:
If your site has traffic don't post any more links.
Don't spam like crazy.
Don't spam fast.

Please share you don't / fails.

Anyone?