If you can drive to within an hours walk of a crag do. Don't decide that the cumulative driving and walking time would be the same as walking from home and embark on a 2 and a half hour snow bash to get to your route.
Don't drop your leashless tool down a bottomless crack half way up a route with darkness clipping at you heals in part due to lesson 1.
If you have yet to take heed of lesson 2 make sure your headtorch works before you attempt to finish your route with one axe. Climbing in the dark with one tool and no torch presents a challenge.
If you have yet to take heed of lessons 1,2 and 3 make sure you are climbing with Brian Davison who it turns out is quite good at climbing in the Dark with no torch and only one axe, He also still uses leashes so there is no risk of him dropping his. If you have fallen short on lessons 2 and 3 steal his torch and ice axe and make a B line for the top of the crag leaving him to deal with the aftermath.
If you failed at lesson 1 it is a long walk down without a torch.
Today I learnt these lessons on the first winter ascent of Hangover, Dove crag. It was a long walk in from Ambleside, I dropped my tool down a big crack, my torch didn't work when it got dark and it was a long walk home. It was a good route and I'm sure in the not too distant future I'll decide that I had a good time.
Conditions were quite good the turf was dry frozen which made things a bit precarious at times. The snow on the fell tops has consolidated quite a bit with the wind throughout the day. The paths low down are very icy.