This is a simply and most common sence guide.
Step 1. Make a lvl 1 named Bank-something
Step 2. You post the item your trying to sell on AH. (works better with high lvl gear)
Step 3. Go on your main and spam WTB [item] 1-2k higher than your own on ah.
Step 4. Ppl will think that they can make some easy money on your item on AH and will go buy it and will try to sell it to your main. If someone /w go check AH if your item have been sold. if it has go use my "my best freind" FAKE DC! ;D
Example. You put [Battered hilt] on ah for 10k. You log on a bank spam trade WTB [Battered hilt] 12k. Someone go buy it you got 10k