At the moment, as soon as 1 or 2 my stones come into direct contact with enemy stones and a fight breaks out, I feel lost. I can usually see about 8 possible moves which look reasonable to me, but I have no method for judging how they compare.

Trying to read out sequences is difficult, since for each of my 8 options I see 8 reasonable replies, and so on, and the number of combinations rapidly becomes unmanageable in my head.

I have tried to learn from studying various sources, but I have not found anything that fills the gap between:
- Re-wordings of the fundamentals: what is a liberty, what is an eye, what is ko, what is a ladder, that sort of thing; and
- Series of numbered moves which have little commentary other than a conclusion at the end that ‘black is better’, and I don’t see why (and I usually think the opposite ).

There seem to be so many conflicting objectives for each move: create liberties, reduce enemy liberties, connect your stones, cut the enemy stones, don’t allow yourself to be cut, leave eye-space. For every reason I can see for a move being good, I can see an equally persuasive reason why it might be bad. I often end up blindly playing a nobi or a hane, simply because I get the impression they are usually safe choices.

So, how to get started on this? Is there a guide out there that explains every move in a sequence, fully and using quite basic ideas? What are the main guiding principles? Are there any rules that work 90% of the time (if this..., do this...)? Is there a method that players use for each move, such as analysing liberties or aiming for one of the ‘good shapes’?

I have tried to learn from studying various sources, but I have not found anything that fills the gap between:
- Re-wordings of the fundamentals: what is a liberty, what is an eye, what is ko, what is a ladder, that sort of thing; and
- Series of numbered moves which have little commentary other than a conclusion at the end that ‘black is better’, and I don’t see why (and I usually think the opposite ).

"How do you fight" is a crazy broad question.

What worked for me was when I was unsure what was going on, I would just fallback to extending my stones. When my opponent attached I would just nobi. Soon you learn that if you can hane instead, you should ... But "Can I hane?" is sometimes a difficult question for players at all levels.

1) Reducing the number of moves you consider, by applying general principles. This means you know where to start reading, to the point where your 8 reasonable responses boil down to two or three of which you can read a satisfactory conclusion.

To address points 1 and 2, I'd read the James Davies' books and do a lot of fighting tsumego, respectively. That's what I've been doing lately and it helped.

- continue to play games, post them for review

Keep playing! Remember the 100 games rule. If you can't prune the tree at all when reading, you'll benefit more from practice than from anything else. Easy tsumego will help too; try the beginner collection on sensei's library.

It may seem insulting when people go on about what a liberty is and what a ladder is, but do you count the liberties on your stones while you wait for your opponent to move? Have you ever read out a ladder that wasn't on the board yet, and played a ladder breaker for it? If you try to do these things, even if it seems hard at first, it will be good practice.

Davies tesuji book is his best, IMHO, but all of them are good (if not necessarily at the level that you want yet).