With every girl, the best thing to do is to compliment, flirt if possible, and after that spend time with her (Also the Offer to Help is good, but it depends on the girl). Since your current energy only lets you talk with 2 girls per day, I will go to just do the talking part with a girl, and then go and do the same but ending with the spend time.
I don´t want it to be a grind game, so later I´ll be adding more scenes and stuff to do to win more points.
About stats, there are barely things to raise them, some scenes raise some of them. It´s a thing I have to work also before starting the advanced game where you need them to grow your relationships. By now, the most easy one, is going home and do exercise with Nicole to raise your resistance.