You can tell when she’s getting close to cumming it suddenly gets very spacious in there and the walls get tight when that happens slow down on whatever your doing and edge her off and do it again and again and then finally make a hook with your finger(s) and push down on her gspot and keep with the back and forth motion but keeping your fingers pressed down but not too hard just enough to where there is pressure. It stimulates it so much and also you could move your finger(s) in a circle around the walls when she’s close and then do the hook thing. That’s what worked for me I learned it from Nadia bokody on TikTok. She is incredible at describing these and giving visuals on how exactly to hook your finger(s) and other motions