Either way, the important part is to be confident and genuine.
When going to networking events, it can be tempting to spend time speaking to people you already know.  Remember your aim, and make sure you speak to people you haven’t met before. Don’t be afraid to introduce yourself to people –  I find a smile, handshake and brief introduction such as, “Hi, I’m Adrian, I don’t think we’ve met yet,” can often be an easy way to strike up a conversation.  You might also want to consider how you introduce yourself, and some networkers advocate using an ‘elevator pitch’ (a short polished summary of your role and/or strengths).  Either way, the important part is to be confident and genuine.