Get naked and lead him to the bedroom to get things started

You undress completely and open the box, letting the superhero inside step out. He's just as naked, and isn't surprised at your state of undress.

"Hello there, buddy. You seem excited to see me." He says, referencing your hardening cock that's been growing since you first looked at Cap.

"Indeed I am. Now, let's get started." You answer and grab his hand, leading Steve to your bedroom. You drop down onto your bed, Cap following suit on top of you, and you begin making out. His hands hold your waist while yours rubs his chest. You're both hard now, your erections rubbing against each other.

Steve stops kissing you and asks "What do you want me to do?"