Check the auroras activity the night of the session. There are many different resources for checking aurora activity, depending on your location.
It is usually best to aim for nights with a KP rating of 2 or more; otherwise, you won't see many auroras in the sky. The aurora activity index (Kp index) ranges from 0 to 9, with 0 being the least amount of activity and 9 being the highest. Kp ratings of 5 or higher are considered a storm.
You will need to find the shutter speed that works best. This is the most important variable because you won't know the lights' speed or brightness until you see them. As a general rule of thumb, if the aurora you see is bright and active, try a shutter speed between 5 and 10 seconds. Between 12 and 20 seconds is a good starting point for a slow-moving aurora, and for a dim aurora, you can increase the shutter speed to 20 or 25 seconds.