We're going to advise the 3 P's
- Plan;
- Prepare (for the worst); and of course
- Pray
Plan
TFL have clearly stated that the Central, DLR and Jubilee line are going to be jam packed and all other lines are going to be busier that normal - so whatever line you're using, leave plenty of time and this tool is a must: http://www.getaheadofthegames.com/travelinaffectedareas/city/london-public-transport.html#
Prepare for the worst
It breaks on a normal day when no-one's even on the train, so let's just multiply that by a few 100! There's not much we can do about things like signal failures, but carrying a bottle of water will really help! Even if you can handle oven-like conditions, that passenger looking a bit faint might appreciate it - and I'm sure everyone using the line will too!
Pray
I'll leave this one to you. Alternatives included crossing your fingers or carrying a lucky charm but be warned, if your lucky charm is a bicycle or suitcase... you will not be liked!
Good luck and God save the Tube!