for next time: if your hive is about to swarm imminently- you can do a Taranov split. This type of split closely resembles a swarm- and the bees think they have swarmed. It is perfect for a hive that has queen cells already and is going to swarm sometime in the next few days or week. It enables you to ensure the old queen goes into the new split without having to find her. Though it looks quite dramatic in practice it is easy and the bees do not get upset.
you can see what one looks like here: