My husband and I are not swingers but we partake in p4p with other females. So my perspective and experiences might not be that helpful in terms of starting the conversation about the topic of swinging with your wife. But on the other hand, I can share with you a female's perspective on how the conversation of playing with other ladies came into our marriage.
I've always enjoyed and appreciated the beauty of a female body but never had the opportunity of being with a girl before I got married. From the very beginning of our relationship, my husband and I have always been extremely honest about our views, ideas and feelings in general, which is one of the reason why I feel p4p is working for us. As
@whocares mentioned, communication is extremely important and the key to all successful relationships especially those that may involve a third party. Beyond being honest and communicative with each other, we started really slow by going to strip clubs to see if I would enjoy it and if I had any issues seeing my husband with another lady. I discovered that I was turned on by the touch and feel of women, but I also experienced an uneasy feeling when I saw other women grinding on my husband. I am not a jealous person at all but I had to mentally and emotionally choose to get over the uneasy feeling to continue to explore further and get to this point.
Some might say this is silly but during the first year of our p4p activities, my husband and I agreed that he could do everything with the girls except have intercourse. The reason for this is because my husband wanted me to feel 100% comfortable and know that there was zero pressure from him to do anything beyond my comfort level. Mentally I thought I would be okay seeing him have sex with another woman since I didn't experience any jealousy during the other acts. But until you actually witness it, you can never be 100% certain of how one would react or respond emotionally. Since we created the space of honesty, respect, love, understanding, patience, and zero pressure from the beginning, at some point during our p4p journey I felt comfortable enough to explore my husband having FS action. Now, in our p4p activities there are no restrictions on what he can do but our ground rules at the moment are we only do FFM or FFFM and we only play as a couple.
At the end of the day, we are both clear and agree that our family and marriage is the most important and our number one priority. We view our p4p experiences as something that is fun we do together and it truly gives us pleasure and happiness to see the other person happy. Also keep in mind that it is not something that is supplementing anything that might be missing within our marriage. If one of us decides that we no longer want to continue, we are both fine with this decision because we truly are 100% satisfied with each other sexually, emotionally and mentally. I believe that everyone and every couple should try to explore sexually but if you are married with children, you need to do it responsibly and with a lot of communication. So my advice is to start a conversation with your wife by checking in with her about her views and feelings with the status of your marriage. If you think you are satisfied with her answer and you are comfortable bringing up the idea of experimenting perhaps ease her in by making a suggestion to go to a strip club. Also, take yourself and your own desires out of the equation in the beginning and make it all about her and how this will be fun and pleasurable for her. I hope this helps and good luck!!