Start by marking out an area of 2300 x 1800mm on the site. These are posts outside dimensions and mark out the perimeter of the frame. You may choose to use a string line. Dig post holes to a minimum depth of 600mm. They should be dug in each corner and two should be placed 700mm back from the front edge, which is where the veranda will join. If the posts seem to be sinking in uneven ground make sure there is plenty of the post sticking out so any extra can be cut off later. Secure the posts using set concrete, follow the instructions on the concrete bag.
Attach the beams to the outside of the posts to form the perimeter frame. Ensure these are level and provide a step up of no more than 300mm from the ground to the top of the beam. Connect two 150 x 50mm cross members, one behind the veranda posts at 700mm and the other at 1800mm from the front bearer. Nail these into the end grain from outside the beams.