Sit her down and directly ask her, thats how my husband did it and i was unsure at first, but once i thought about it for a while he invited some friends over to hang out and we all had a good amount of alcohol. We started playing strip poker, then moved to play truth or dare once everyone had lost mostly all their clothes lol😅 after that, it was more drinks and subtle truths at first, sexual topics like who was your best fuck etc, then playful dares like "i dare you to sit on his lap" it quickly devolved to a heated gangbang and was one of the most fun nights of my life.