Vegetable Garden Fence Design with 2x2 Posts
I will line up all the posts, measure, mark, pre-drill, and screw in all the brackets before the posts ever go into the ground.


What if you can't drive one all the way to your predicted depth, or what if you drive one your predicted depth and it is not yet stable and you want to drive it further? I would not pre-attach your rail brackets or I bet they will not end up straight/level.


  Do I slope my fence or do I make sure every post top is level with every other? 


Slope the fence, 1/2" per foot adds up.


  boards around the bottom of the fence for additional structural support, to withstand some extra impacts


Unnecessary for impact, unless you expect charging cats and hedgehogs to head-butt the fence. But it might add some extra stability.