Worthwhile to learn for yourself even if you hire someone—bad pruning is ubiquitous in the tree care industry, even by so-called professionals. Keep in mind that trees don’t need pruning for their own sake. So before doing any pruning you want to have a clear goal in mind. A young tree that you can reach from the ground is easy enough for a layman to prune if you do your research. If it’s bigger I might hire someone but ask questions and ensure they have the proper certifications: ISA in the US.