Opener's 2♠ is forcing to game, and North encourages because the hand is strong: good diamonds, a singleton and a losing trick count of eight.
Plan the play.
Dummy's club length is annoying. It looks like we have a club loser as well as ♦A. We could discard a club from hand on one of dummy's diamonds if only we had an entry.
But we do have an entry. We can ruff a heart! That means we need to delay drawing trumps and we need to set up the diamond winner immediately. So take the first trick and lead a diamond to the king. Let's say that East covers with the ace and plays a second round of clubs. We win, cash the ♥A, ruff a heart and discard a club on dummy's ♦Q. Then we draw trumps and lay the hand down.
The important point is this. Ruffing a loser with long trumps does not (in itself) gain a trick. Ruffing a loser with short trumps does gain a trick. Ruffing a winner with short trumps neither gains nor loses a trick, but it may gain you an entry.