[Noble713]

Select the ship you want to lead the formation and press Alt-# (#= group to lead). To add ships to the formation select and press Ctrl-#. I've had some problems with doing this manually, though. Sometimes all the ships in the formation will try to move to the edges of the map no matter where the leader goes, and other times they leave gaps in the formation. I think formations are a great feature with some serious potential, but like most of SE4 *cough* AI *cough*, it needs to be refined.