Sounds like you just did. You just need a little more of a topic.

With a little more than the obvious..

The weather. Or something you have in common.

Smile, Hey there, how are you? Did you have a nice Christmas and New Year? I like your shoes (shoes are good therapeutic devices). What have you been up to today? Other things are active listening, which is a skill, taking a genuine interest and expressing warmth and compassion.

In what sort of situation?

I always think smiling is important--try to look like you are really interested in the other person. Then of course say hi or whatever. If they're a stranger it's hard to come up with much else to say though, isn't it? Complimenting something you like about them (shoes, hair style or whatever) is pretty safe. If I can't think of much to say I try to ask them questions about something they're interested in that I either don't know much about or are, on the other hand, also interested in. Finding a common interest early on in the conversation is very helpful.

Try to avoid negative stuff as well as religion or politics if at all possible.