Step 4: Hanging the gate
First, is to simply position the gate as close to where it's supposed to go so you can eyeball it. Look at it's squareness or take note of any potential problems that might hinder the gates operation. Now look at how you're going to be able to hold it in place while you actually attach the hardware.
What I've done in the 1st photo is set a temp nail in one of my 4x4 posts to keep the gate from falling forward through the opening. So far so good.
Next, I used 2x4's on the ground in a position so as to leverage the gate at it's proper height.
My final nifty trick was to use a single shim to go between the gate's opening and 4x4 post. A gate like this is pretty heavy and will tend to lean towards the opposite side of the hinges. Therefore, you want to make sure there will be some clearance for the gate to smoothly open.
While I didn't take a picture during the process of installing the header, now is a good time do so, if your gate is going to require one. The 4x4 post, while strongly set in concrete, is still not enough to keep it upright and true without some sort of additional support. Since my GF doesn't want me to build fencing on that side, I explained my woes to her and she agreed to installing the header. The header is the support running along the top .
Make sure your tops are level and equidistant to the measurements taken at the bottom.