I accept most of the friend requests (except those who have a private profile or a vac/trade ban) but make sure you tell me the reason why you added me.
Also, don't break any of the following rules:

Rules
First talk before trade (Do NOT instant trade invite on me, I hate it).
Do NOT beg for stuff.
Do NOT invite me to groups.
Do NOT add me back if I rejected your invite or deleted you from my list.
Do NOT ask to change my inventory privacy. It will always stay on private.
Do NOT spam me with messages; (avoid writing one word on a single/each line).
Do NOT constantly invite me to games.
Don't try to scam me, you'll waste your time.