Took me ages to pluck up the courage to do it, now it's second nature.
The 20/20 rule is one I always stick to, and the most important rule (already been brought up), is just stick to what you feel comfortable doing!
Good to know about not passing the first car; I generally pull over in front of the first car in order to put myself in a visible and therefore safer position. I'll re-consider from now on! Is this true for all lights where pedestrians can cross, or just lights which are there solely to let pedestrians cross (toucans, pelicans etc.)?
