1) The Sarcasm: Sarcasm generally translates poorly over the internet. Unless your sarcasm is original, just keep it to yourself. No more "Great win tonight, we have a winner in Bronco. If you want to make a point, try something new like "Bronco sure knows how to coach his teams for cold weather. Yep, those Savannah S taters looks like they weren't prepared for the power of a Wasatch!" See, that's funny. What you said wasn't.

2) The Pigeon-holing: Not everyone that wants to see Bronco gone is a whiny, perspective-less, unhappy curmudgeon. Likewise, not everyone who thinks Bronco should stay is a happy-go-lucky, football illiterate, peter-priesthood type person.

3) General lack of civility. Just be nice, unless someone is a jerk to you, then be a jerk back. Don't call people names. That isn't nice. If someone calls you a name, then consider whether or not they might be right. It may be time for a lifestyle change. Also, don't argue.

4) Beating dead-horses (I realize the irony here): Don't bother repeating the arguments of others. Either offer a fresh perspective on the matter or don't bother. Horse-Beating on Cougarboard is well documented, but if you want a quick guide on topics that don't merit lengthy discussion, here you go:
Net vs Gross
In-n-Out vs 5 Guys
Bronco is a terrible coach
Bronco is the best BYU can get
Blue shirts vs white shirts
Homeschooling your kids (for or against)
Indy vs MWC
Nick Howell isn't qualified
BYU had a chance at the Big12 (I can FEEL it!)
Friend of Scouting (Thanks 93 Cougar!)
And many, many more!

These are the subjects you should just generally avoid. Unless you actually are smarter than most people, then you should really opine. We are dying to learn what you can teach us.

5) Unwillingness to consider other's perspective: put yourself in the shoes of the person you are debating and you experience will dramatically improve. If you notice the debater isn't willing to do to the same, move on. If trolling is your goal, then this tactic can be incredibly effective against the right subject (give it a try!). You would be amazed and the level of frustration you can get out of people by appearing to be sincere.

6) Grammer Jerks: I am looking at you, CarolinaCoug! It's the internet; people are lazy (and stupid). Just because you recently learned the difference between their, there and they're doesn't mean you need to be a show off about it (don't act like you knew the difference all along). On the other hand, if you actually know what the difference between effected and affected is, or what the crap a dangling participle is, than disregard this advice. You deserve to be snobby about grammar and the world needs more people like you patrolling amongst the commoners.

Anyway, just some late afternoon ramblings. Feel free to correct me on anything incorrect that I said. Also, if I contradicted myself anywhere, you really should let me know. I, like most people, love to be corrected. Thanks!