With more than four in suit, lead king after queen.
With only four or three in suit, lead ace after queen.
Ace, king, queen, with or without small ones (in plain suits).
Lead king, then queen.
Ace, king, knave, &c.
Lead king, then ace.
Sometimes it is right, more especially in trumps, to lead king, then to change the suit, and to finesse the knave on the return, particularly if queen is turned up to your right. With more than five trumps it is seldom advisable to wait for the finesse. No positive rule can be laid down, either for trumps or plain suits.
Ace, king, and small (in trumps).
Lead king, then ace, if you have at least five small ones. Otherwise, lead a small one (the fourth-best if an American Leader).