How to efficiently attack castled king in here?

Hi everybody!

Recently I'm improving mostly with studying short opening lines, doing a lot of simple tactics and studying some basic endgames. However, one of the things which bothers me the most is attack to a castled king - sometimes I simply see the solution, make some sacrifice and everything works, but sometimes, like in this case, I thing I'm better (definitely around moves 20-25), while I'm definitely not and my opponent has time to coordinate their defense. Also, when they blunder, usually I don't spot it with respect to the castled king at all, as the combination seems too long.

Does it come only to precise calculation or are there any heuristics or general rules, I could use in my game to see the real situation?

Thank you very much for every advice!

Yes. Precise calculation.

Sacrifices always take precise calculation. General rules will be weak.

Pure math; how many attackers do you have, how many defenders do they have. Here they're able to get more defenders than you'll have attackers. You've got the queen, maybe a pawn in two or three turns, a knight in three turns, a rook in three turns. They've got a pawn and knight in one turn and a rook in two. There's no fast win here.

Standard rules apply; if you can't outspeed them, then attack with your weakest pieces first. Better to attack with your pawns than with your knight.

You don't have a chance to break the pawn formation here, which is the best bet for a sac exchange. Making the pawns stagger like on move 18 is good, it makes it harder for them to defend each other, but the main checkmate into staggered pawns requires a queen and either a bishop or a pawn on the sixth rank.

Pins are good. The queen on g4 is pinning the g pawn, but it's also pinning the e pawn to the knight, and making it harder for black to push the f pawn which would leave the e pawn undefended.

That's about it for general rules. Got to calculate.

There are general rules look-up books like "Art of Attack"; "Art of Sacrifice" etc. the combination needed here is easy you sac the rook with queen beside it, that pawn being your post. Capitalize on black's mistake on move 24 rather than your blunder of move 25. Or even the suggested move c1 diagonal =mate.
Attacking a castle is a matter of the tactic called defelxcion+ sometimes sacrifice, The first or most general rule is " once you attack it is a commitment any going back is a loss. All and every posted defense usually a knight much be moved out then bang OH.

Agree that the Art of Attack is a good book, and at least parts of it are sufficiently concrete that it should stick with you. Excellent section on bishop sacrifices for example. Never read Art of Sacrifice.

In the game, at move 20, it was fairly obvious to me that there was likely to be nothing if you didn't weaken the pawn structure with h4 as recommended by the computer. And absent computer analysis, I'd have thought you were losing, as there just arent a lot of pieces left, no open file, and you cant stick the knight on f6. 23 ... qb6 was a steaming turd of a move -- that attack is going nowhere if you cant get the queen to h4.