So maybe you want to play. But you don't remember how. It's been a long time. You can no longer rely on people helping you go to the bathroom, or maybe you can again. Okay, time to break out the amazing and long-forgotten skill of playing.
If you're a typical MMO player, you just thought of something you want to accomplish in an MMO. Wrong! You are thinking of accomplishments, where the goal is to get something. No. Imagine that you just found out that there's going to be a server rollback tomorrow, everything wiped. What do you want to do now? What would be an end in and of itself, not a means to some other end?
Well, don't just sit there reading some stupid web page. Try it! Go do something fun. Not something that you do for tangible rewards, not something that is there to improve your character; do something that is fun in and of itself. It's okay if rewards happen, but you should be doing something that you would do even if the rewards were all gone.
Okay! Here's where the magic starts happening. If you actually went and did something fun, you'll have enjoyed it. You'll feel, not like you got something done, but like you took a bit of a break and relaxed. Now, think about what you did... And do it better. Same activity, but do it better. You were AoE farming? Farm bigger groups. Exploring? Get somewhere even harder to get to. Looking for great screenshots? Get better ones. Running instances with friends? Do them better. Fewer deaths, clear faster, or heck, just have more fun joking around. Figure out what you were doing, and do it better.
Sometimes you may not really feel that this is applicable. That's fine. Doing something you enjoy just because you enjoy it is also okay. You'll still be learning even if you aren't really pushing it. Maybe you'll learn to do things in a more relaxed way. :)
Here's the cool thing. If you've successfully improved at whatever you were doing to have fun, you will now have a weird new experience. See. You had fun. You relaxed. You weren't working. You accomplished something anyway. You learned something. And you learned it better than you would have putting the same amount of time into "studying".
Okay, this is the big one. Don't expect it to click all at once. You now know what it is like to learn by playing, to have fun and somehow come out of it better off than if you'd "worked". Now, the magical thing: You can learn anything this way, if you approach it as a fun thing. Wanna learn a programming language? Don't sit there struggling through exercises. Write something fun. Make a game. Make a silly program. Do something that is fun. Play.