Notch out the deck posts 120mm x 20mm up from the bottom. Or, to make this part of the project much easier and faster, you can buy these pre-notched. If you need to extend your notch further then do this using a handsaw or circular saw. Ask someone to hold the deck post in position whilst you mark the location of two evenly spaced pilot holes on the post. To fix the deck posts to the bearer, hang washers on the end of a 130mm exterior coach screw, then tighten the screws with a socket set Use a tape measure to make sure deck posts are evenly spaced, with a maximum distance of 1800mm between them. If you want the post to be flush to the decking then you will need to notch it into the decking. Start by marking out where the post will be onto the deck and the fascia. Put the post into position and check that it is flush to the decking. Then, secure the post as before and reattach the fascia. To make sure spindles are placed evenly, measure and cut a piece of spindle to 81mm and use this as a marker. Measure 81mm from the end of the rail and use a try square to mark an accurate line. This line marks where the first spindle will be placed. When you are marking the bottom railings, m...