Unzip wetsuit as you exit water. Take one arm out at a time and run to your bike with it half off. Once there, keep pulling wetsuit down by rolling outward with 2-3 good ‘snap pulls’. Now the tricky part – roll wetsuit outward as far down each ankle as possible .  One leg at a time – Stick both thumbs between wetsuit and heel and slip wetsuit under heel. Then ‘snap pull’ wetsuit off your leg by grabbing calf area.
Some athletes like to try to put vaseline or pam spray on their legs to make the wetsuit slip off easier, although, I have had much success without using a lubricant.
Each time you exit the open water during your practice swims, you should practice a quick wetsuit exit.  It gets easier the more you practice!