Taking a Sim on a date for dinner is a great way to make a friend. Why? Because a 3-course meal takes a long time to eat, giving lots of time for the two to chat about interests. If the conversation starts to take a nosedive, change the topic. It never hurts to take them shopping and have them try on clothes usually boosts fun and friendship points.
A tip from a forum member will get a large group of friends in no time.
"Have one of your sims in an empty neighborhood (this only works if you have Hot Date, Vacation, or Superstar) and get them the genie lamp. When they wish for love, they will fall in love with a townie. When I have done this, they ended up with 40 friends!" - ELLENCZ
