I set an advert up for my wife on a swinging site. It said she was reluctant but I had strong desires. Posted it with a bikini pic (not showing face. Then went in the chat rooms and drummed up responses. Got a portfolio of 53 interested guys face pics.
Told her I had done it just for fun and showed her the advert and the responses. Instead of being mad she admitted she was flattered that so many had contacted her (didn't tell her I had chatted to many in rooms)
A few days later she agreed to give a mmf a go and we went through the candidates and she chose her top couple. I then told her number one wanted her to send some pics. I would take some but she could decide which three to send.
She dressed sexily and as I snapped away got more daring until she had her titties out, then her pussy showing. She picked one of her dressed sexy, one showing her titties and one of her pussy....saying it's what he really wants to see.
Whilst I sent them She started playing with her vibrator. It had got her hot.
We did meet him, and he did fuck her...another story though. You might want to try something similar!