If North rebids 3♠ based on shape rather than Points then NS probably reach 4♠ and given how hard it is to make probably regret it

North counts 4 losers. One Spade (assuming 3-2 split), Two Hearts, and a possible Diamond.

It rarely helps to ruff Dummy's losers in Declarer's hand,

A Diamond lead saves declarer a guess, and a Spade lead aslo helps Declarer

Both a Heart and a Club lead should end up with Declarer in Dummy

Then Declarer should play for split honours in Spades and finesse twice, This avoids losing two Spade tricks despit ethe bad break

South is a little weak for a traditional 3♥ pre-empt vulnerable but the modern aggressive style works well here keeping E/W out of a Spade slam

Against 4♥ tight defence is needed. 

West should start with the ♣ K. It is normal to play 'King for Count' and West is more interested in Count than Attitude to tell her whether it is safe to continue Clubs. When East plays the ♣ 3 they have either one, three or five Clubs. Five would mean South only has one and would be ruffing the second round.

West can let the Clubs wait and switch to the ♦ 9. This indicates to East that West started with two Diamonds and hence South started with only one.

East can therefore win ♦ A,  cash the ♠ A, and play a Club back to West for the setting trick.