Like all scams, this requires you to take advantage of a persons greed, and a bit of social engineering on your part.
1. Choose an NPC trade item that isn't being sold in your region
2. Buy a large quantity of that Item and ship it to a system.
3. Put the item on market for double, triple, whatever the cost you paid for the items originally
4. Setup a buy order about 6 jumps away in a system with little to no traffic for 'x' ISK
5. In the system where you put the stuff on market, ask in local if you can borrow some ISK to do a highly profitable trade run.
6. If someone bites, eventually tell them what item you're going to be 'buying'
7. The person should get overcome by greed and buy the items off market hoping to make the insane profit for himself
8. Once he buys, cancel the buy order 6 jumps away, leaving him with overpriced pieces of !@#$%^&*.
Example:
Buy 10,000 units of 'Amarrian Wheat' for 100 isk each (1,00,000 ISK total) and take it to a region that doesn't sell/buy it. Pick a fairly active system and put the Wheat on market for 1,000 ISK per unite ( 10,000,000 ISK total). Put a buy order in a deserted system for 2,000 ISK/unit (20M total). Bait someone into buying the wheat thinking he would make easy ISK, then close the buy order, netting yourself 9M isk profit. OFC, you will want to sell alot more units and at a greater price, but you get the picture.