I never got anywhere near a path to actual mastery, but I did enough concentration meditation to go into the mind states where I felt like oh, this is what it's

I never got anywhere near a path to actual mastery, but I did enough concentration meditation to go into the mind states where I felt like oh, this is what it's about. At first, meditation was all about just coping with boredom and muscle pain (from sitting still) and trying to return to the breath while thoughts constantly kept emerging. This was not especially fun, but the sheer difficulty of just sitting still seemed to make it a good challenge, like I clearly had a lot to learn. Even during this phase I usually felt better and more clear after meditation, so I liked doing it even though it wasn't really satisfying in the moment. Then over months I started to see what it means to let go of everything except the focus on the meditation object, usually the breath but I also found it very interesting to meditate on the visual appearance of a small unicolored circle ("kasina"). And I learned about jhana/dhyana practice which really inspired me to take concentration seriously. Also I discovered the benefits for meditation of just being nice to people and animals and maintaining a good mood, clean house, etc—reducing ambient stress and "bad karma." Eventually I started to actually get into those jhana states. It starts by getting very relaxed and concentrated and then starting to notice how there are some subtle pleasant sensations around your bodily perception, maybe your belly or palms or somewhere; then you shift your concentration to take that pleasure as its object, which causes it to increase and spread. It's no exaggeration that this can be a state of pervasive sensory pleasure, like your whole body is full of a kind of fizzy happiness. It's easy to get so excited that you fall out of the state, so the practice becomes to stay calm within it. And then the fizziness subsides into a more calm pleasure, and then it becomes not even really pleasure but just contentment like a peaceful lake without wind. By the way concentration in these contexts shouldn't be understood as a kind of forceful and strained effort, rather the opposite. But you probably just have to learn through trial and error. I'd try to write more descriptively but it would probably get long and tedious.