Take plenty of food & drink keeps you warm, alert & its something to do in the slow bits.(no booze, it'll slow your reactions & make you knackered - result you'll not catch as much or enjoy it as much. It's alleged that Carp Anglers reactions resound across the entire country!.
Make sure you leave your swim /peg clean, it's amazing where all the sweet wrappers, fag butts go!
Above all enjoy the experience
& make sure you & your mates car, motorcycle, bike, scooter, rollerskate & other property is secure!.
As Big Rik said, wait until summer for your first night session - the nights are shorter, and usually a bit warmer !! You have to be sure that you will be able to find all your gear in the dark, and be able to net and handle your fish competently.
It really is easier if you start when the nights are shorter. And as an ex-resident of Thirsk, which is not a million miles from the 'Boro, I can remember that summer nights up there are only a few hours long.
My mate found out, by experiential learning, that it's a good idea not to have your bivvy door 3ft away & facing the lake, especially if it's 13ft deep & there's no light. By the same process he also found out 5 mins later that having some spare clothes would have been nice!