How do you get more stars on the sims 3 late night.?

Whenever you get an opportunity on your phone, look to see if it rewards celebrity points. If it does, do it. Also, become close friends with celebrities (other people with stars), marrying a celerity increases it A LOT. Basically just do all those opportunities and interact with other celebs as much as possible.

After you get a lot of stars, be careful about what you do in public. The paparazzi might spread the word and make you a public disgrace. I've been a public disgrace for biting another person in public, woohooing in public, and something else but I forgot o.o'

Yeah, you just need to befriend celebrities. You can impress them with your high skill levels, who you already know, your money if you're wealthy. Once you've impress them, just keep the friendship going and they'll invite you to parties or out. Yeah, but once you're famous paparazzi is everywhere and if you do something bad, you'll lose your friends.