A “Limit Order” is an order to buy or sell a specific quantity of wagers at a limit price. The resulting wagers cannot execute at a price less favorable to the player than the limit price, but wagers can execute at prices more favorable if it is available in the market.
You can put in a limit order and wait for someone else to match you or you can wait for someone else to post orders for you to match.
You would select "Limit" from the order type button located on the right hand side of the order screen.
Listed below are picture and video showing how to place a "Limit Order"