A market order is a basic order type that instructs a brokerage to buy or sell a security at the current market price, prioritizing speed of execution over price certainty.

To submit a market order on the Depth of Market (Ladder), set your lot size under the account tab, and

to go long: click any price above the last traded price in the bid section.

to go short: click any price below the last traded price in the offer section.