When the bees are flying you know its the right time to fool with them. If they'e not flying they're in a cluster trying to keep warm. If you have any more questions feel free. Btw, I would First Id where the hive is for sure, if in wall, they most often, almost always build from top to bottom, so start at the top, and work downwards. Have proper protection, have the right tools and a bucket of water to wipe honey from your tools, like scrapers. A beevac comes in handy on a large hive. If no beevac, spray them with sugarwater to keep them from flying so much and brush them in the box.