What you will need:
Chest, Sign, Redstone and the items you wish to sell or buy.
Step one:
Place chest down with the quantity of the items you want to sell at one time
e.g. For one Sign click, the buyer will get 5 of the items.
Step two:
Place the Sign and type:
First row:[Buy]or[Sell]
Second row: Name of item
Third row: Quantity sold
Fourth row: Amount sold for E.g... $5.00 each time bought
Step three:
Get the Redstone in hand and left click the chest and then the sign. The[Buy]or[Sell]part should turn blue
Step four:
Put all the items in.
Tips:
[Buy] [Sell] Colours
Blue = In stock
Red = out of stock, Chest is full
Grey = Try again!