One little routine I realised I needed during my first year of randonneuring, and which I have continued to do ever since, is to have a 'place for everything and everything in its place'.

If I know that I've got food in this pocket of my trunk bag, tubes in that pocket, etc. ... and if that is always where I keep the food, tubes, etc. ... it makes finding what I need and dealing with the situation so much faster and easier, especially at 2 am, when my brain is feeling a bit fuzzy.