[marrs]

A good place to start is by writing productive code. As part of the development process, look back on what parts of the code are holding you back the most. Perhaps bugs keep appearing in this dialogue, or that list renders very slowly, or setting up the unit tests takes a lot of boilerplate. Something on the project will be impacting your delivery the most. Work out what it is if it isn't already obvious, then fix it. You might do this by using a pre-existing library, or you might write your own solution.

Either way, by going through the problem solving process, you will develop some of the skills needed to recognise the motivation behind the solutions provided by 3rd party libraries and you will be in a better position to evaluate them.