The beginning of the zone is the valve, which is over in Zone 7. We will need to run a 1 inch PVC pipe from the valve over to the corner of Zone 6 where we need it. That is shown in "yellow". Then we can switch to 3/4 inch PVC (in "orange") for the actual zone itself. We will put one head in the middle of the 1 inch supply line. And since the lower left corner where we start the actual irrigation is complicated enough, being both an unusual angle, and having one input line and two output lines, plus a head, we delay converting one of the output lines from 1 inch to 3/4 inch until we get to the next head. We can get a tee fitting that is 1 x 1 x 3/4; I don't think there is a 1 x 3/4 x 3/4.
From this design, we can go buy the fittings and pipe and lay things out. The main purchase at Home Depot was for $125.48. There were multiple additional trips to multiple Home Depots to get all the fittings we needed. But once we had them, we could lay things out and start to trench where the lines will go.
We have 15 heads, plus two bubblers, one on each side of the "tree", or at least where we expect the tree to go.
Zone 6 starts at the valve and extends along next to the Retaining wall to the sidewalk, with one head half-way in-between.
The corner by the sidewalk is particularly complicated. It has a head, plus it goes East along the sidewalk and South towards the fence. It has to do this while missing the main irrigation water supply line.
As it heads South, towards the fence, it makes a little 10 x 10 box in order to (a) cover the center of the zone, and (b) provide a bubbler for where the tree will be planted.
Once it gets to the fence, there is a slight jog to the West, to put in a head
and then straight alone the fence to the electrical box.
The line goes out around the concrete pad that the electrical box sits on, and then heads North across the yard back to the sidewalk. This is designed to be perpendicular to the sidewalk, so there is a bit of an angle at the electrical box, since the fence and the sidewalk are not parallel.
Across the yard to the sidewalk
and then along the sidewalk back to the beginning.