Many species of cypress trees have a naturally pyramidal form, be it a softened pyramid, an elongated one, or a classic rectilinear shape. Common examples of this pyramidal habit are Leyland, Arizona and bald cypress. As a genus, cypress does not require heavy pruning to establish form or maintain its canopy shape but can readily tolerate shearing to perfect the pyramidal form, according to Clemson University.
Remove any discolored, dead, diseased or damaged foliage fronds and small branches throughout the tree with loppers. Cut back to the point of healthy tissue, but no further, in order to preserve as much of the tree's pyramidal structure as possible. Pull all of the loose branches and pieces of cuttings from the canopy and collect them to discard.
Hold the long-blade pruning shears against the canopy roughly parallel with the sloping surface of the tree. Start at the bottom on the canopy working your way up the tree following the natural, tapering slope as you move upwards. Trim off just the branch tips that extend beyond the mass of the canopy to create a clean outline. Reduce the length of the branch tips if you like, to reduce the size of the pyramid, understanding that the tree may look bare in spots for some time but will eventually fill in again. Establish a guideline of the desired shape and size of the tree on one side from bottom to top. Step back from the tree 10 feet or more and look at the shape of the guideline to ensure you like the look.
Step back up to the tree, holding the cutting blade parallel to the canopy. Starting from the newly established guideline, work your way around the tree cutting the branch tips at a depth to match the guideline. Work from the bottom to top in passes. Step back from the tree each time you complete a new line of cuts form top to bottom to inspect your work and refine where necessary.