Get sims to visit another house?

This is a silly question.... I am playing the Sims Freeplay and I can not figure out how to get my new sim to go and visit another sim so they can become friends. I am pretty sure the game told me how because I got one of my 3 sims to visit and become friends, but I can not get my other sim to leave their house to become friends with the other 2.

Thanks