CP1 - When cashing winners in a suit play :
high card (s) from the short side first !
so that you not become cut off from Dummy

Declarer (W)
♠ - A 9 7 2
♥ - Q 5
♦ - A 9 5
♣ - A K J 8
Dummy (E)
♠ - 8 6
♥ - A K J 4 2
♦ - 8 7 4
♣ - 9 7 3

Play the ♥Q from Declarer's hand first, then cross over with Declarer's ♥5 to Dummy. Dummy wins the trick and can now run off all remaining heart winners. (If Declarer plays his ♥Q on the 2nd heart trick, he can no longer reach the three remaining winners in Dummy!)

Here are two more typical card combinations :

♦ A Q J
opposite Dummy
3 5 9 10 K ♦

Play the ♦A and ♦Q in Declarer's hand first.
Then lead the ♦J and take it over with Dummy's ♦K.
Dummy now can lead out the two remaining winners.

♦ A Q
♣ 8 4 2
opposite Dummy
3 5 J K ♦
♣ A

Declarer plays high cards from the short side first, but now can not take over his ♦Q with Dummy's ♦K, for he then will only make three tricks in total.
Declarer must "unblock" the diamond suit, playing his ♦A and ♦Q first (playing low in Dummy), then cross over to Dummy with a small club to Dummy's ♣A.
Now Dummy is on lead to cash the remaining two winners.

CP2 - Preferred LEADS by the Defence
so that Partner's high card is not captured by the Defence

With Dummy on your left : lead through Dummy's strength

With Dummy on your right : lead around to Dummy's weakness