Depends on what you mean by giving a haircut. Don't go
@Vapo style on them this late in the grow. Go slow...start from the bottom and work your way up.
Look for leaves that are in the shade, these ones will probably not produce enough energy and removing them will create more space for air to move. Remove small side shoots with tiné tiny flowers in the lower parts. If no light reaches them, they will produce nothing worth keeping and the energy is better spent on other nodes which are more promising.
Thanks mate. I always am mixed about what to take off.