I'm glad you didn't bust out the cards on the first day and introduce yourself as "Mr. Magic" to everyone.
Find an effect like Woody Aragon's 10 card poker deal and do it for a bunch of friends on a weekend night. "I'm sort of feeling lucky tonight... anyone want to play a game?" Make the introduction offhand and seemingly not about magic. Have a follow up like Sankey's Carbon Paper (anything using a lighter is cool) or something that is most definitely magic. Mention that your a magician and that you haven't done a lot of performing since you were just getting used to being at college. End it there (or depending on your mood, mention that you also know "dark magic" bruhahahahaha). When friends ask again, say "maybe this weekend" or if it is the weekend "maybe later tonight." When they ask again, perform two more effects.
Follow John Bannon's rule... make them ask twice before you perform (Bannon might be three times...). Perform when you want to and on your terms. Also, follow Eugene Burger's model (which is explained in Darren Brown's Pure Effect) which is to make it an experience. Give it importance, "is everybody ready, because I want to show you something really special. Let's begin." or something to that effect.
If you don't want to perform for friends, go to a park. People are generally just waiting around in the park and are easy to approach.
Nursing homes are a great idea (as mentioned above) and great experience. One time I was doing a show and setting up. One of the female residents came up and mentioned how much stuff I had. She asked how I keep track of all of it. I told her that I had a list, but inevitably I forget something. She laughed and asked me what I forgot for this show. I told her that I had forgotten my belt (which was true) and joked that if my pants fell down during the show, she would know why. She smiled and said, "that might be the best part of the show."
