Light meters for the most part don't work at night. Although if you can get a reading from yours. You'll have to check the reciprocal values for the film you're using. You can google them. It should come up with what the meter reads and then the value you multiply by and then the corrected exposure.
A lot of the time when you shoot at night. It requires a lot of experimentation. Make sure you take something to record your exposures with.
As someone as already pointed out, shoot it with 35mm before hand, using the same film you intend to use on the night.
Check out The Nocturnes

Hope this helps.