For this trophy you'll need to complete the normal campaign in order to unlock New Game +.
But before you start NG+ I highly recommend getting all, or most of the perks unlocked on your first play-through , as NG+ lets you keep your unlocked perks (as well as purchased weapons and veichels).
By the way you can still upgrade some perks when playing NG+. So check there regularly.
Weapons I used are:
•SA-50 "FREE STATE", modified with a long range scope, suppressor square and an extended magazine.
•.44 Magnum L, modified with a reflex sight.
•M133
•AR-C
•Flames on Flames (or any of the other two).
•Rocket launcher
If you want your own different set of weapons you'll need to look at how much damage each one causes, and choose the ones that are the highest. Also keep in mind modifying is also an option (which I recommend).
Always keep two companions with you.
Going around the regions are easy enough if you have the patience and correct weapons. But when it comes to the bosses, keep these in mind:
When fighting John Seed, invite Nick Rye. He'll take him out within a minute or two.
Faith Seed. You can use your second weapons wheel by holding L1 + R1 to consume speed and aggression. This will help you a ton.
Jacob is a lot more difficult.
The trials you need to try and try over again. Memorize where the enemies are in each room. The video I've linked below will help with that.
His boss fight is easier though. Bring a rocket launcher to take out those speakers from a distance which will also take out the enemies there too (maybe not all). But don't forget you can use the speed and aggression from the second weapon wheel.
As for the bunkers for each enemy listed above, I recommend taking your time as there isn't a time limit. Again, don't forget you can use the aggression and speed stuff if need be.
At the end of the game, you must press X for resist. I didn't get the trophy if I press O (walk away). If you do accidentally press O, you can exit to the main menu after the credits and press continue. This will direct you back at the point before you dealt with Joseph.