I have no problem helping with this, but it's strange you'd make yourself responsible for this outcome.
It can be very difficult depending on who the recipient is. Let's just be blunt about this, if they can't get a relationship themselves then there's a reason for this. If they're ugly, socially inept or have some sort of complex that results in self sabotage, a love ritual can be very difficult or even impossible frankly. You could do a ritual that brings an ideal partner to their front door (theoretically of course, practically unrealistic), and if they can't muster the confidence to greet them it would be pointless. It's possible you'd have to influence both the ideal partner and the recipient, something perhaps you might be interested in but I could never be bothered.
Getting a gf/bf isn't really something one should need a ritual for unless they are a special sort of desperate. If you want it bad enough, you go out and meet people, and you face the possibility of rejection as an acceptable risk. Having a ritual work without effort on their end probably isn't happening unless you're like kundalini ascended or something, which if you were you wouldn't be asking silly questions like this here.
The best advice would be to keep an open mind on how "love" is interpreted. Love doesn't have to be just sex, it can be self love, it can be affection expressed by family or even a friend. Maybe this person isn't actually ready for a sexual relationship, even if they think they are--- if they were, they wouldn't need you to compensate for their short comings.
Good luck on this, but I have to admit I think you're wasting your time here unfortunately.