Always use the gun shop
Before any mission you play, find a local gun shop ASAP and make sure you have proper body armor. Also, having a large supply of ammunition for your gun collection is the first thing you should think after making sure you have on a vest. This will be key for when you’re on the last bar of your short health indicator and are franticly running around to conserve energy in the middle of a shootout. Our suggestion would be stocking up on Grenade Launcher and Sticky Bombs, whether you’re out in the open land of Blaine County or in Los Santos.