Sometimes it can be easy to spend more time doing than planning. We don’t often take time to plan as comprehensively as we could.
But time spent planning is incredibly valuable.
When you have a head full of things that need to go into a project, actually planning the project will free cognitive space, enabling you to get on with completion and other jobs on top.
It will also help you to better estimate the amount of time and effort that you need to devote to each task.
The sheer complexity of modern life means that unexpected events will often disrupt your plans. That being said, maybe instead of "unexpected", we should say "expected". Rather than being thrown off course, and seeing them as setbacks, we should plan for the unexpected.
Be as flexible as you can. Build in extra room for manoeuvre. Make contingency plans. If we know how rarely things go exactly to plan, we shouldn't plan that way.
See how much flexibility you can build into your plans. It will help you stay on course when things pop up.