Lessons I have learned on the train(s):
1. When your gut instinct says "don't put your favourite umbrella that your sister bought you and you only use when you want to look gorgeous while trudging through the rain" in the luggage rack, DON'T put it in the luggage rack. You will forget it there are dwell on your lost umbrella for days to come. It will also pour for the rest of your trip leaving you looking less than gorgeous while trudging through the rain.
2. When making the inevitable dash for your train be sure you put the correct ticket through the barriers before charging through. They will not open with a very used and very old ticket. You will be stuck. People will look. You will feel stupid.
3. Read the platform carefully. Very very carefully. 11A and 11B are two very different platforms with two very different trains. Sprinting down the platform 11 and jumping on the first train you see won't go as smoothly as you may hope.
4. When attempting to run from one train to another in less than 30 seconds be sure to be the first person off the train. Do not get stuck behind an 89 year old lady with 2 walking sticks and a desire to have a chat with the ticket collector directly in the door of the train. It isn't the most time efficient way to exit the train.
5. Don't assume that you correctly remember your departure time from when you booked your ticket months ago. Your memory isn't very good, not very good at all. You will end up being "that" woman running through the station shouting "excuse me, excuse me, MOVE" because there is no way you are paying for another full price ticket!