This is not 'Nam, this is Fandom; There are Rules

You know how people say "the clothes make the man?" Well, in a certain way (and if I'm permitted a shameless rhyme), you can amend it to say "the clothes make the fan." Those of us who call ourselves devoted sports fans end up dedicating a significant portion of our wardrobes to attire of our favorite teams. Just like anything else when it comes to fandom, there are rules to be followed when wearing fan attire. I've touched on this before, but at this point it seems something more along the lines of a manifesto is warranted. (And for the record, that is a picture of Brady Quinn's sister Laura, now married to AJ Hawk, at the Fiesta Bowl 5 years ago when she wore the half-Brady Quinn, half-AJ Hawk jersey you see there and became an overnight celebrity thanks to ABC's camera crew. I just wanted to include that picture because I find it funny that she and AJ Hawk probably pretend not to be home these days when Brady calls or wants to stop by. You can imagine it.)

-No cross-pollination, aka wearing two different teams' gear at the same time, unless extreme circumstances call for it. This especially goes out to people who wear an NFL jersey with the hat of the favorite MLB team. Focus on one at a time.
-If attending a game, positively do not wear something that depicts a team from a different sport from the one you are witnessing. No Eagles shirts at Phillies games, no Mark Sanchez or Eli Manning jerseys at Yankees games, etc. One exception would be if attending a college game and wearing apparel of a different program at the same school, i.e. an "XYZ University Basketball" hoodie at an XYZ University football game.
-Avoid wearing multiple articles of the same team's clothing on non-game days. The "decked out" look works for a kid, not an adult. Once again, this is only on non-game days.
-Keep things as authentic as possible, within budget of course. I'm not telling you to drop $175-$200 on an authentic baseball jersey that is so nice that you feel obligated to carry it around in a garment bag (although if you have the means, I highly recommend picking one up), but let's stay away from the Wal-Mart jerseys that make you look stupid. And if you happen to root for a pro team who goes NNOB (no name on back, in uniform speak), then you shall not wear a jersey with a player's name on the back. Obviously with NCAA jerseys it's a different story because you can't buy those jerseys with player names on the back. Since the other three major leagues mandate names on the backs of jerseys, baseball is the only sport where this really comes into play. Mainly, this is a memo to fellow Yankee fans out there: if Derek Jeter simply wears the #2 on his back, then all you should be wearing is the #2 on your back. I'll gladly make an exception for the player t-shirts with a name and number on the back - those are fine. But a jersey with an unwarranted name on the back? Not fine.
-Another big issue while we're on the topic of authenticity: no hats, jerseys, shirts, or anything else that is not in team colors. I can't stress this enough. It's fine if you're a girl and you like Shane Victorino and want to get his jersey or t-shirt; just make sure it's not pink, green, black, or any other color that Victorino himself does not wear out on the field. And do not get me started on the 67,000 different colors you can buy New Era baseball hats in now. I don't care if you want a jet-black Phillies hat because it looks better with most of the clothes you wear. The team chooses their colors, not you. You choose to root for that team, then you commit to those colors. End of story.
-I shouldn't have to say it, but personalized jerseys with your own name on the back are a no-no once you pass age 10.
-Since that last item was definitely the least original in this post, I'll now offer my most original. Say you own the jersey of a player who no longer plays for your team. As long as he is still active and playing for another team, you have to mothball the jersey. You give off an air of indirectly rooting for another team if you continue to wear the jersey. Once that player retires, you can go back to wearing that jersey if the player was worthy enough. As much as I loved my Jason Giambi Yankees t-shirt, it's just best for everyone if that thing stays at the bottom of the drawer while he's still playing elsewhere. Once he retires, the shirt can go back into the gym rotation. A major exception would be if you choose to wear the jersey as a silent protest of your team letting that player go. An example of this would be if you were a 49ers fan and kept wearing your Jerry Rice jersey during his "oh, I guess he wasn't washed up after all" productive few years in Oakland immediately following the end of his 49er days.
-On the matter of throwbacks: toe the line carefully. One time in college, I spotted a kid on campus with a sweet powder blue #19 Lance Alworth Chargers throwback. I stopped him to compliment him on the jersey, but more importantly to ask him what, if anything, he knew about Lance Alworth. I don't even need to tell you how underwhelmed I was by the response. If you are going to wear a throwback, then come prepared with a respectable level of knowledge about whichever player you're wearing. Can't guess within 20 of how many home runs Mike Schmidt hit in his career (548)? Don't know which Super Bowl Roger Staubach was named MVP of (VI)? Then don't wear the jersey. Because I'll find you.

I'm sure there are things that I've left off the list or that you may disagree with, so have at it below if you are so inclined.