If you are one of Ben's students, look at his Steve Huber banjo maintenance lesson.
If not, do a Google search and find a Youtube video with someone doing this. Seeing is always better than just a text description.
You will need to be able to tighten or loosen the nuts. Don't use pliers! You need to make fairly small, consistent adjustments and pliers will not be accurate enough. There are nut wrench tools to do this (if you can find a drum key that will fit, that would do the trick).
When you do adjustments, make small ones. One-eighth turn maximum at a time (thus the nut wrench). Adjust one nut and then adjust the nut on the other side of the rim.
If you number the nuts 1 to 24 (assuming there are 24 nuts) going clockwise around the rim, then I would start doing 24 then 12, 1 then 13, 23 then 11, 2 then 14 and so on. You want to try and keep the tension consistent as you make your adjustments so you can't do one 'side' (say nuts 13 to 24) and then the other and be accurate.