Don’t get stuck with people who will hold you back, or allow your success to depend on that of other people. Be conscious of your helpers and your hinderers—make time for the former, and appreciate the modern convenience of caller ID in screening out the latter. Build a diverse network, and attend functions and events so that new people can get to know you.
Make a list of upcoming events that are relevant to your career goals, and create an action plan. List your objectives for attending. Going with a purpose will instill more self-confidence. If possible, get a list of the attendees in advance. Once you know whom you want to meet, use the Internet to brush up on background information so that you feel more comfortable when talking to them. Use LinkedIn to find out whether you have any mutual friends or acquaintances. If so, ask for an email introduction before the event, or ask the mutual acquaintance if you can use their name to introduce yourself in person.
As for getting through the events themselves? Don’t worry about talking to everyone—just deal with one person at a time. Have several questions ready to kick start conversation (Have you been to these meetings before? What brings you here, or what keeps you coming back? How have you benefitted from these events?), and do your best to listen more than you talk. Everyone loves to feel heard—and you’re likely to learn something if you allow yourself to absorb.