I do some night fishin' but not always for crappies. Cats and walleye move at night.
I am a coon hunter so I use my coon hunting light for seeing in the boat. I always use a red lense. It doesn't spook fish and more important, it doesn't draw insects. My coon hunting light has a spotlight. I rarely use the spot light but there are times it is worth it's weight in gold.
This is just my personal opinion but I think a person should be a skilled boatsman before attempting night fishin'. Too many things can go wrong. If you are a beginner, stay close to your dock or ramp.
Bring a GPS and make a waypoint where you start.