Hi Tami,
The easiest way to check your air assist pressure is to press and hold the shift button (arrow up key on your machines keypad) and then press the fan button. This will manually turn on the air pump. Now you can have the lid open to check the pressure. If it needs adjustment you can open the right side panel on the machine with the pump running and adjust the white knob on the pump.
If you have any questions send me a PM.