Find a subject that you love and learn as much as possible. Once you have done so, find someone to teach.
The act of teaching forces us to articulate our understanding. If our students do not understand, that is the main indication that our understanding is not where we think it is — or should be.
There is a tendency of overestimating our understanding. No one wants to admit to being ignorant. That is the wrong perspective.
Ignorance is a shining light. Ignorance is a guide. Find a stumbling blocks. For where you fall is where you need to get up. Once you find your feet again, then you know that the path has been advanced. That is until you fall once again.
There’s the beauty.
The path never ends. All that we can find is refinement.
Would you want it any other way?