It was so easy to make friends during my undergrad because I lived in the dorms. But I lost half of them due to a messy situation with my ex girlfriend, and the other half doesn't live in town anymore.
Now I'm 22, working on my Master's, and I feel like I have no one.
If you are a small talker, ask for the person's phone number at the end of the conversation and send them a message a day later and ask if they want to hangout. Prime locations are coffee shops, grocery stores, airports, and bus stops but you can do it anywhere really.
My wife and I make majority of our friends this way.