Went soft during my last couple of hookups, and I don’t want to bust out half-pipe on this girl again!

Mental connection to your partner? A good diet? Being well rested? Vitamins? Sufficient foreplay? Being very hydrated? Simply not overthinking? I’m sure it’s a combo of all, but if you could give ONE high priority tip, what would it be? What’s the #1 best thing you’ve found that contributes to staying hard and erect during sex. Thank you for any answers or suggestions!