I got invited to a Lunch and Seminar event from a Internationally well-known IT Company. I checked the schedule of the event and saw a time for "Lunch and Networking". I think this will be the one of the best opportunity for me to meet people that i can be friends with, ask advises for my career and also a good job opportunity. the thing is i don't have any ideas to approach and befriend these people to that event, of course the speakers and attendees will be mostly middle-aged man and have this professional look.

Currently I'm Computer Programmer (7 mos) to an Industrial Engineering/Manufacturing company and this is my first job, I'm 21, finished my bachelor's degree last year and i still look like I'm my teens(Some people still say i look like a student and in doubt I'm currently a working professional)

How can i approach these people and make use of this event to the fullest with my current standing? This will be my very first Professional event in my very first months in my career-life. I need to get use this remaining months and get ready to the outer world of my career.