It depends how long you can wait that an order is executed into a fill. If time is critical you can only pay full spread via market order.
By full spread, do you mean when bid is 20.92, ask is 20.94, you're paying the full 0.02 for immediate execution? I thought it would only be 0.01 from last price.

. When you send a market order, you're paying for the entire spread, whether that's 0.01 or 0.25 (like right after FOMC meetings). If you dont' wanna pay the spread, use limit orders. It's as simple as that.