In human computer interaction they often talk about the "gulf of execution" - when the desired end state is known but it's unclear how to get there.

https://en.wikipedia.org/wiki/Gulf_of_execution

I've found that using checklists helps tremendously when working on medium to large projects (things that take more than a weekend to complete).

For example, if I want to learn a new technology, maybe I'll get a book on python, add the list of chapters in my projects tracking document, and strike them off one by one.

That sense of steady progress helps tremendously.