I have always been a big planner, but I have planned to be flexible.
My style of planning is: today I am going to achieve this, that and the other — then I recieve a phone call/email and that all changes.
In the back of my car I have a drawer with 2 spare sets of clothes (training gear and nice casual gear, food, tool, medical kit etc… I also have a pillow, sleeping bag, matress, picnic mat and tarpoline. I bring my laptop EVERYWHERE and often have approrpriate stuff located locally (eg websites that I am developing are on my hard drive).
Read more: Luke Freeman - Why Should I Plan?