Make sure that the posts that your picket gate will be attached to are in-line with each other, 1 against the house and the other against the boundary fence. Hold the set square flush to your brick wall with a piece of wood underneath it. Lift the piece of wood and set square up, so that they're flush with the brick wall and the boundary fence. Mark this off on the fence and the wall. This is where you'll be putting your posts.
Take your spade and dig individual holes underneath the marks on the wall and boundary fence. They should be deep enough to support your gate posts.
Put the posts in the hole, in-line with the marks on the wall and fence and use a spirit level to make sure they're straight. Shovel the cement into the holes and let it set for at least 24 hours.
Mark 3 spots on the post next to the brick wall, one near the top, middle and bottom of the post, making sure they're in the middle of the bricks.
Use a spade drill bit to drill about 30mm into the 3 marks you've made on the post. Then use a wood drill bit to drill into the 3 holes in the post but don't drill into the bricks. Do this by making a mark on the drill bit at the depth you want to drill. Using a masonry drill bit, drill through the post and into the bricks. Hammer the Dynabolts into the holes and use a socket wrench to secure the post against the wall.
Use your tape measure to measure the distance between the 2 posts. Measure it at the top and the bottom of the posts to make sure it's square. This distance is the length you'll be making the horizontal bars of the picket gate.
Mark out the distance between the two posts on the 3 metal horizontal rails of the gate frame. Clamp the rail to your sawhorse and cut each of them to size with a hacksaw.
Assemble the frame for the picket gate, using a hammer to gently tap the rails into place. Secure the joints using a drill and the screws that have been provided.
On the post attached to the brick wall, mark where you want the picket gate's frame to be. Make sure you take into account the height of the pathway below, so the pickets don't scrape against it.
Hold the gate frame against the post and drill a screw into the top hinge. Check that it's straight with your spirit level and then drill a screw into the bottom hinge. If necessary, undo the screws on the bottom hinge and adjust the gate frame so that the gap between the frame and posts is the same distance.
Mark this distance out on each of the 3 horizontal rails. Use a drill with a counter sink to drill the holes in the pickets. This will stop the wooden pickets from splitting as you attach them to the frame. Screw the pickets into place on the top and bottom rails using your frame marks as a guide.
Once you've attached all the pickets to your frame, it's time to slot the gate back onto the hinges.
After attaching the gate frame back on the hinges, you need to cut the posts. Measure about 2 centimetres above the height of the pickets on both posts. Because of the height of the posts that you're cutting, it's safer to use a handsaw to cut them rather than a circular saw.
You're now ready to attach the gate latch.