I've spent most of my studies focused on learning proofs of theorems, as that was what took the most time to learn well enough in order to do well at exams. After seeing how some mathematicians I know are able to solve some problems with ease, I've started trying to improve my problem solving ability and general control of a topic.
The first goal I set for myself was to go through Isaac's Finite Group Theory, and do all the exercises. But I'm not sure it's working well enough for my goal - after doing the exercises in a few of the sub-chapters, I still feel like if I were to given a similar type of problems as the ones I did, I would probably not be much faster than I was when I did the first set.
My aim isn't to just somewhat understand the topic, and feel like I can do the exercises - I want it to become something relatively easy, that doesn't take effort, that's almost 'intuitive' in some sense, and that I can do it without much focus.
But I don't know whether it's a good idea to aim for this so directly - maybe it will just (hopefully) come with time as I improve generally and get a slight understanding of some topic... but I have considered that maybe I should just do tons of exercises of a given type, until it becomes easy and fast, and then move on, rather than moving on after I do the exercises at the end of a chapter.
Also, I do ask my own questions concerning the topics, the exercises, and play around with it a little bit, but only as much as I feel like, as I enjoy it more to just move to the next exercise - which might not be enough.
I would appreciate opinions on whether trying something like this (very large amount of exercises of 'similar' difficulty and topic, and possibly even repetitive practice of a certain type exercises) is a good idea - and whether even directly trying to get control of a certain topic is a good goal, etc.