To complete this achievement you must do both The Fleeca job ( First Heist ) and The Pacific Standard Job (Fifth Heist). You do not have to do the second, third and fourth.
The final heist ends after jumping off the cliff on your bikes and parachuting off them and land in the water. Once landed in the water or safely on the ground, get into the boat and sail up to the bridge and the heist will be complete. The achievement will be unlocked after the cutscene with Lester and been returned to freeroam.