Hi Trey,
I have a couple of suggestions. With the suit on, zipped, and cuffs rolled under as if you are ready to go diving. Before you put your hood on, put one arm around your waist area, with the other hand open the neck seal and take a deep bend at the knees. Prior to standing let the neck seal close, then stand. This will do a very good job of expelling most of the air. This technique is used frequently with drysuits. Another option is to try and expel the air through your arm. Underwater raise one arm to the highest point and slightly open the wrist seal. This should help a little as well. It may take a little moving around to shift the air towards the wrist, but if done properly it will allow the air to escape while not letting in water.
I hope this helps.
Best,