How do you keep up with making sex interesting

A blindfold or using even just a handkerchief (or the cheesy handcuffs) to tie their hands together adds a different feeling & sensation. Use more foreplay & take your time. Demand your partner do certain things to use or use a toy during foreplay. Do it in a different room or location such as over the arm of the couch or on the washing machine. Wear a skirt & sneak in something naughty when you're not at home.

I haven’t run into this problem but I did tell my husband I’d like to try some light bdsm but like on him. Like dominatrix stuff and his vanilla ass said idk about that lol