I just don't want to break any rules.

For my starting items, feats, skills, and flaws, do I just put them in my signature myself or should I post at the sales counter and "buy" my beginning item/spell/weapon/skills/feat/flaw

You may place your starting items in your signature all on your own, there is no need to buy them as you have little to no gold as is. :lol: You do not need special permission from the sales counter unless you would like to purchase more than what's allotted to you as a beginner.