No trump: loading honors and returning the suit (Friend's view)

'Me' at the bottom is the viewpoint player; P2–P5 are the other four seats.
Setup

Mighty Basics Replay. This game is from the Friend's view in no trump. The declarer P3 won the bid at ♠13, then switched to no trump, raising the contract to 15. I hold the Friend card ♦A, so I'm the Friend. The only card in my hand that can win is the ♦A; my other honors can't win on their own. Honors like these only score if you load them onto the declarer's winning tricks.
Trick 1

The declarer opened with the ♠K. I had no honor in that suit, so I played a low ♠5.
Trick 2

The declarer led the ♥A. All my hearts are honors, so I loaded the lowest one, the ♥10.
Trick 3

The declarer continued with the ♠Q. You can see this is a long-suit game, with the declarer holding many spades.
Trick 4

The declarer led the Mighty. A sure trick for us, so I loaded the ♣10, a card that could never win on its own.
Trick 5

The ♠10 is a boss too. I loaded the ♣J as well. Now the declarer alone holds spades.
Trick 6

The declarer led a low ♦9. Leading the Friend card's suit is a call for help to me. I took it with the ♦A, revealed myself as the Friend, and gained the lead.
Trick 7

This is the Friend's most important play in the game. Leading any of my other cards could hand the lead to the defenders, so I immediately returned the diamond the declarer asked for, with the ♦2. The declarer's ♦K became the boss, and the lead went back to the declarer.
Trick 8

The declarer led the Joker and called spades. A sure trick for us, so I loaded the ♥J, reaching 15 points — the contract.
Trick 9

The declarer's ♠6 is a boss too, as one of the remaining spades. I loaded the ♥Q.
Trick 10

On the last spade, the ♠4, all the boss cards the defenders had held to the end came tumbling out.
Result

20:0, a run. I won only one trick, but all six of my honors became our points. In no trump, the Friend's job is less about winning and more about loading honors and returning the requested suit. You can step through this game yourself in the Basics Replay section of Mighty Korea's school (mightykorea.com).