I have been learning a lot of cool stuff from books I've been reading and lectures I've been watching but I'm finding it hard to apply what I learn in games (finding the next big move, finding the correct way to respond to a play) that I play because I feel pressured for time. I suppose I could ignore the game clock and spend all the time I need to find a good move, but at the same time I'd rather not keep losing due to running out of time. Is there any way to work on improving (on average) the amount of time spent thinking per move? I'm not sure how to do that in my games or in tsumego.

One possible way would be to play games with no main time, but long byo-yomi periods, and slowly reduce the amount of overtime. For example, start with 5 periods of a minute, then 5 periods of 40 seconds, and so on. I'm not sure what would be a good place to stop, but this will definitely be able to get you to play more quickly. However, so this doesn't lead to you not thinking, it might be a good idea to only play moves in the last ~5 seconds of the period, no matter how obvious the reply seems.

I lost a lot of time just plain doubting between options I didn't know the consequences of. So now if I can't see where it leads, I just pick one, and eventually it becomes quite clear whether I should choose the same way more often.

Also, especially in a game, if you can't see it clearly from as far as you can read it out, trying to read one stone further is a gigantic waste of time and effort. You run low on time, get tired, and for all this, you don't actually have a guaranteed better move.

One other way to cut down on time wasting during games is to do lots of easy tsumego, so you don't have to spend time on the simple stuff anymore.

For tsumego, many not too hard ones is better than few which are very difficult. If you spend more than 5 minutes each on several problems in a row, get an easier set and do that a few times before coming back. I definitely DO NOT mean to say you should give up on the harder ones, just that you should train up before trying again.

I actually recommend quick games (since there is probably a major difference in your play based on the time controls, I recommend making a new account specifically for this)

Come to grips with the fact that your rating on this new account will be considerably lower at first, and force yourself to just play the natural moves that occur to you. You will get burned, a lot. But over time it will begin to come naturally. When you return to your other account, 30 seconds byoyomi will seem like a lifetime.

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Tactics yes, Tact no...

You need a reason why you choose the move you want to play. If you don't know why you played the move you chose, or couldn't come up with any other alternatives, then it doesn't matter how long to take to play each move -- more time just won't help then.

Play quickly (not blitz, just don't take too long to think about it*). Then review your game thinking about why you played certain moves -- especially the ones that didn't work out well in your favor. Try to find a better move. Then play that in your next game.

Eventually you'll have reasons for your moves (even if those reasons are initially wrong, they can be corrected with review and practice). And with reasons for your moves, you'll be able to play quickly enough to not lose on time.

* but only you, knows how quick is too quick, and how long is too long. (well, maybe your opponent might know how long is too long too )

Hmm.. that's interesting. It seems that most people are suggesting that I play more fast games. But like xed_over says, I feel like it's important for me to have a reason for the moves I play. Won't playing faster games just force me to rely on my intuition rather than well-thought out play?

Not sure what your level is, but thinking longer isn`t necessarily going to mean better, especially since we`re not quite 9p yet

A lot of go is played by feel, which comes with experience, rather than thinking out a logical reason. As shapenaji says, play the natural moves that occur to you at the time. Your feel will improve as you go along. Watch a few high dan level games online, see how quickly most moves are played, even at that level.

Also, one way to look at the game is to ask yourself where your opponent would like to play next, if he could move right now. See if you can find a reason to play that point, and take it away from him.

There is a lot of value in just seeing things happen. For instance, you might play 2 15 minute games where a situation comes up, get it wrong the first time, think about it a bit (or even just not do so but remember at the back of your mind), then get it right the next time. This might be, in this case, as valuable as playing one 60 minute game where you thought about the move a lot to find the right answer - but it actually took twice as long to get it right!

As a specific example, you mention playing big points as something that you have learned about but find difficult to put into practice. This is something where reading will not really help you - it almost certainly isn't actually good enough to really understand where the game will go over the next few moves, especially since you're unlikely to predict with much certainty where your opponent might play. Instead, playing a lot of games and seeing what happens in certain shapes when you (and your opponent) try different ideas actually teaches you a lot more about this sort of thing, more quickly.

This isn't to say that this is the only way to learn things, or even that it works for some concepts, but I think it is very valuable to just see a lot of situations quickly and gain a feel for them. Reading might help you in an individual situation, but overall this more quickly exposes you to the wide range of ideas that you need to become stronger. Long games most certainly develop other skills, and have their own place.

As always, YMMV.