First and foremost, trade at your own risk. Reputation is everything in trading circles. Invite Friends to start trading, extend your circle as you meet people who are trustworthy. BeerXchange tracks all trades and user ratings so good traders stand out and you know who you are dealing with.
If you are new to trading start small by offering beers that are local to you that do not distribute widely. If you have access to whales you can easily trade for other highly sought after beers. Don't expect to land a whale on your first try.