I once did an international camping and backpacking trip like this where we had everything down to a minute.

The key is to check your watch after you complete any activity. For example, you read that a 1000ft climb hike takes 2 hours and you do it in 2.5 hours.

Do this over months and you gain the ability to make perfect estimates. Turns out that feedback loops are useful.

Also applies to all other skills.

Funny thing is I’m mostly a buy tickets to fly next week and wing it kind of person but I wanted to try it one time for kicks. Winging it is a whole different set of skills. Get good at both and planning becomes your jam.