I find that when I try to speculate on price, I always lose. So I just buy and sell at market price now.
there's usually a 0.1 USD spread or so going on. More often than not, placing a bid/ask and waiting for a bit works out just fine.
Only if I really want to sell/buy I take what the market offers.
I suppose I just find it not worth it with the amounts of BTC I am dealing with. It'd be like $2 or something, and I didn't really care about trying to make that much, so I just buy or sell it immediately.