The term geek was originally meant to be slang, for the people who were odd and were not a part of the mainstream. Well back then, not being a part of the main stream was a bad thing. And now, it is the ‘coolest’ thing to do. Therefore being a geek is also kind of considered to be in fashion now. but the problem is in order for not to be mainstream, you need to know something about the alternative, as only thick rimmed glasses will not make a you a geek. That will merely make you look like one. So if you are really keen on not being ‘mainstream’, try knowing a little about all geeky stuff.
To be a proper geek, well for once, you have start watching movies and TV shows that have been labeled as ‘geek movies/TV shows’ unanimously. Star Trek, Star Wars, Stargate, Monty Python, The X-files- you have to be extremely familiar with all these and remember all minor trivia.
Remove your Windows operating system and install Linux. Learn a thing or two about hacking. Learn to ‘jailbreak’ an apple device. There are many more of such things related to computers that you really need to know in order to be a proper geek.
remember, for a geek, the computer is the world. And also the internet. Learn how to use the internet in the ‘geeky’ way. use a proxy server for anonymity. Create a basic website using a notepad only. Play snake on YouTube.
Also get your conception of heroes and villains absolutely clear. For this you have to go back to your geeky movies and check all the men there.
Having proper knowledge of comics and gaming is very crucial too. Otherwise, you do not qualify as a geek.