You should start off small and build your reputation (feedback) by buying 10-20 cheap items over 1-4 week period. Then, sell off 10-20 items as auctions (anything really, things from your house etc.)
When you're done, start selling whatever you want BUT just one thing at a time for 2-3 auctions. Then, you can gradually increase the number of auctions.
This is a pretty safe way to avoid account suspension.