Advice for selling on eBay?

Hello
I found this forum not long ago through my mom and gotta say I love this board already. Pardon me if I'm posting this in the wrong section.

Since I'm a stay at home mom with some extra time on my hands, I want to contribute to the household income but I'm really new to the whole making money with eBay thing. All I have done so far is to order some eBay moneymaking kit from a site called My-Ebay-Moneymaker after reading a review about it here.

I'm still learning the ropes of selling on eBay, but would like to know if anyone here knows of any pitfalls I should be aware of. Return policies and foreign customers is one hassle I have heard a lot about.

I would love to hear some feedback on this.
Thanks!