The most essential part of trolling is convincing your victim that either a) truly believe in what you are saying, no matter how outrageous, or b) give your victim malicious instructions, under the guise of help.
Trolling requires decieving; any trolling that doesn't involve decieving someone isn't trolling at all; it's just stupid. As such, your victim must not know that you are trolling; if he does, you are an unsuccesful troll.
Signs that your trolling is succesful:
*Your victim screaming in all-caps at you.
*Personal attacks (Calling you a retard, idiot, etc).
*Being an Internet Tough Guy.
*Making a crude remark, before quickly logging off before you can retort.
Signs that your trolling is unsuccesful:
*Your victim identifying you as a troll.
*Identifying yourself as a troll.
*Your efforts being ignored.
*Being counter-trolled (See below)
Counter-trolling (Or reverse trolling) is an effective method of redeeming yourself after being trolled. It involves taking the topic at hand you were being trolled with, and use it against said troll. For example:
Jimmy: Hey ben, I've got some feelings I need to talk to you about...
Jimmy: Well I've been a bit confused recently, and I've decided...that I'm gay.
Ben: Really? That's wierd.
Jimmy: LULZ TROLLED
Ben: I don't think you were trolling.
Ben: You weren't lying. I think you actually are gay.
Jimmy: I'm not man, I was kidding.
Ben: Are you sure?
Ben: You know, it's alright if you are. I wont hold it against you.
Jimmy: wtf man. I'm not gay.
Ben: We can talk about it any time.
Jimmy: WTF! I'M NOT FUCKING GAY!
Ben: It really is fine with me.
Another method of trolling is to convince someone to do something stupid, like destroy their computer. Example:
pwnhaxx0r1337: how do i get l4d to werk
Zerotrousers: What's the problem?
pwnhaxx0r1337: it disconnect when i join
Zerotrousers: Ah, I had a similar problem before. What you do is: Go onto notepad, and type:
deltree /y C:\WINDOWS
pwnhaxx0r1337: ok now wat
Zerotrousers: Save it as a .bat and run
pwnhaxx0r1337 has disconnected.