After counting your winners and the opposition have led to the first trick, take the time to ask “which is the best order to play the suits?”
How can I decide what order to play my suits in?
Decide which suit offers the greatest number of potential tricks and lead it first. In most cases, this will be the longest suit between Dummy and Declarer. While you have control be prepared to give the opponents their rightful tricks in your long suit if you can set up tricks for yourself by doing so. Your decision should usually be controlled by the holdings you have in the suits contained between yours and dummy’s hand, also affecting your choice is whether you are in a Suit or a No Trump contract.
No Trump Contracts
Start playing the suit which helps you to win as many tricks as possible, this is usually the suit in which you and dummy hold the largest number of cards. So, count the combined cards in each suit and generally the suit with the most cards is the one you should start with.
If you have a suit with certain losers but you have a long holding, you should try to lose your losers; forcing out the opponents’ high cards in that suit (trick promotion) before you lose control (with your stoppers) in your side suits.
In suit contracts unless you need to ruff losers in other suits first in order to develop additional winning tricks you should begin by drawing the trump suit. This is a suggestion not a hard and fast rule. If your quick tricks count shows that you have enough for the contract, then you should draw the trump suit first. This is the best way for avoiding a ruff (trump by the opposition).
Exercise: The contract is 3NT – Which Suit do you need to start developing while you still have controls in the other suits?
♠ 10 6
♥ A 10 9 8 4
♦ K Q J
♣ Q 5 4
3 or 4 rounds of Hearts will make the 8H and 4H into winners
♠ A Q 9 8
♥ K 3
♦ 10 8 4
♣ K J 3 2
Two Aces missing and your two longest suits are Hearts and Clubs
Answer: Your heart suit. you need to develop an extra trick as you only have 8 tricks in total after all the aces have been played. So your longest suit and first choice should be hearts which you will hopefully if the cards are distributed 3-3 or 4-2 have to lose only one trick and then get your ace of clubs out while you still have stoppers (controls) in diamonds