Cut back privet hedges twice yearly, once in mid-spring and a second time in mid- to late-summer. Cut out damaged branches at any time.
Prune out dead or winter damaged branches by cutting them off where they join with the nearest healthy wood. Use a small pair of pruning shears so you can easily reach into the interior of the shrub to make these cuts.
Trim back the top of the hedge to the desired height, removing up to a third of the top growth. Use hedge trimmers to make a slightly rounded, even cut. A slightly rounded top allows the hedge to more easily shed excess moisture and snow.
Cut back the sides of the privet hedge with the trimmers, removing up to a third of the side branches' length. Slope the side down slightly from the top, so the top is thinner than the bottom of the hedge. This allows sunlight and moisture to reach the lower branches.
Inspect the hedge for aberrant branches producing the dull gray leaves. Cut these branches out completely at their base.