First: Any girls potential sex appeal is what it is. You can't raise it above her potential, so obviously you'll have to get a girl with a potential sex appeal above 70 first, preferably a divine girl.
Landing such girls can be a bit tricky. Adding points to your seduction of course helps, being really shitfaced drunk all the time helps, throwing and going to parties helps, having the maybach car really helps.
When dating check the girls temper (hoover her pic) and choose your pickup lines accordingly, temper below 34 use top line (friendly) 34-66 middle line and 67-100 3rd line. Always make sure your first pickup line works by checking the meter. And when she wants a gift be sure to give it to her. Alternatively you can just give her the high heels (2 CC) and close the deal right away.
Then you max out her stats in the gym and add treatments in the spa till she has reached her full potential.
