What is the most logical next event?

How to trim overgrown boxwoods
Remove dead or damaged branches from the shrub first.
These branches should be easy to spot-the leaves will be shriveled up and brown, and the stems will snap easily. Use sharp, clean pruning shears to snip off the dead sections, making the cut at the base of the branch.
Make sure you look at the interior of the shrub for dead or damaged sections, not just the outer parts of the shrub. Watch out for signs of boxwood blight.