Don't choose the guy for her.....if she is really into it she has her own ideas of the dream guy she wants to fuck...I know from experience....you want her to enjoy it to the fullest so you can too.....so you should sit down with her and find out the kind of guy of she wants....maybe she wants some romance to go with it...in which case she already has a list of guys in mind...it could be a co-worker, her boss, a neighbour, a relative, one of your friends or co-workers....or an absolute stranger....before you embark on this journey you want to get off to a good start...so lots of communication and rules between you and lots of love and trust.....or it will go south on you in a hurry