Small Heart from North taken by the Ace in dummy.
You can see 2 Spades, 2 Hearts and a Diamond.
You have to find 7 tricks from the Clubs.
Small Spade to the King and back to the Ace.
Another Spade, ruffed by South with the 8, over-ruffed with the 9 of Clubs.
Heart King, discarding a Diamond from dummy.
Now a Diamond to the Ace and another Diamond, taken by South's Queen - no room to lose any more....
South plays a Club to 5, Queen and King.
Now another Spade, ruffed with the 10, over-ruffed with the Ace.
Small Diamond, ruffed with the 2 of Clubs.
Jack of Clubs takes out the remaining trump and then dummy is good.
12 tricks and small slam made.