So here goes the first step! Tell your wife you want to have a date night. Take her out. Have a good time and a couple of drinks, flirt with her, compliment her and make her feel sexy. Then, when she is relaxed and happy tell her that you want to talk about your sex life and how you would love to please her by doing what makes her happy. Ask her what her idea is of the perfect evening leading up to sex and then ask her how she would LOVE to be seduced by you, what she would like you to do. Get all the details. Take it all on board and remember everything. The next time you make love (hopefully that night) do everything she asked for. Then do it again.
When she is totally spent, tell her that you should do it on a regular basis - you should have date nights. Then suggest that you can alternate between her desires and yours. Now is the important part... you have to say how much you enjoyed this evening and how different men and women are when it comes to sex. How women are more emotional and men are more physical when it comes to turn ons and how nice it would be if she could try and do some things that turn you on.
When asked what turns you on - be vague. Keep on safe ground. Say you like it when she dresses up and talk about how exciting it was when you first met and maybe she can pretend that she has never slept with you before and it would be great if she can flirt with you and try and seduce you. Tell her it would be like when you first met, exciting! This will make her very receptive. Once you get her to agree, then make your next date (at home).
As the day draws near tell her how excited you are and ask her what she is going to wear. Talk a lot about what you want. Tell her, as you will (hopefully) be alone and undisturbed at home and that this is about you, maybe she can wear something revealing and no underwear and act a bit sluttish in her attempts to seduce you. Tell her that you would love that. Ask her if she could talk dirty as well. Tell her to try and be a bit of an actress. Now is the really hard part (for me anyway) DO NOT masturbate or have sex for a week before hand, you want to build up your sperm bank to the maximum - this is very important - when you cum she has to notice a huge increase.
On the night have fun - don't be pushy and make her feel like she is doing well. When you make love talk dirty but keep it about only you two - "Do you love my hard cock inside you?" "Tell me you want my cock" "beg me to fuck you" Get HER to talk dirty to you. Then cum everywhere!
When she comments on how much you came - act embarrassed and confide in her that an erotic image just "popped" into your head and caused you to explode! She will immediately ask you what it was. Tell her you can't because you are too embarrassed. She will cajole you to tell her. Tell her that you are also worried it may make her cross. Make her believe it is really bad without saying so. She will start offering suggestions as to what it could be. If she mentions another women say that it is worse than that. Eventually tell her - but build the moment - the *reluctantly* tell her that as you having sex and she was saying all of those wonderful things to you an image popped into your head of her mounting a huge cock and her face was in ecstasy. Tell her that when you saw her fucking another man it had the weirdest effect on you, that you felt jealous and scared - but it was the most erotic sight in the whole world and at that moment, seeing her having such pleasure made you have the most intense orgasm of your life. Watch her carefully for signs. She will be one of three- 1 neutral, 2 disgusted, 3 encouraging. Whatever frame of mind she is in, agree with her - say you are so embarrassed and don't know why the image popped into your head, but also ask her why she thinks it made you come like that. Tell her you find it really weird. Try and explore it with her. Tell her the jealousy and fear of loss really enhanced the experience for you. Like an adrenaline junkie. See how much she wants to discuss it - let her lead. When you are done talk about her next date night and what she would like - make it all about her again.
All we are doing here is laying the foundation. Putting the thought out there.