Selling on ebay.

I've heard some bad things in the last few years about selling on Ebay, mostly sellers being ripped off and such. Does anyone have tips on how to not get screwed over, as well as how to get attention and sell my stuff on there?

I have some things I need to get rid of (my own sewing projects, as well as stuff I bought that doesn't fit anymore) and craigslist wasn't working for me.