A lot of people seem to be confused about what they can and can't wear while riding outside. Here's what you need to know:
Really the best option is to get on a decent local team and only wear your team kit while riding in public. Understandably this can't always work out, because not everyone has the time to join a good team and buy enough jerseys to wear every time you leave the house. If you can't, you're still okay, just follow these guidelines...
The only acceptable shorts are bibs. This is because bibs are infinitely more comfortable than shorts, and because bibs eliminate the ubiquitous back gap that must never happen. The only acceptable color for bibs is black. I know that plenty of professional teams have non black shorts but you aren't on one of them and we don't want to have to see your junk when you're fumbling with your seat bag at the 7-11 before the ride. I wish I could forget the image of Boonen's weiner in that green jersey, but he's Tom Boonen and if he wants to show off his weiner, that's his decision to make. Win a green jersey and I'll stop telling you what to do. If your amateur team has non black shorts, you need to find a new team. I'm looking at you Spine&Sport. Note that's it's ok if your side panels aren't black as long as the front and back panels are. See CU and DU's team kits:
I know this is a hard one because there are so many awesome jerseys out there that you really think need to be seen by the general public, but the ONLY acceptable jerseys are solid colors without writing on them. This means that you can't wear a jersey with your favorite beer or band from the early 80's on it. In addition, nobody gives a fuck that you finished the triple bypass in 1997. Unless you're doing it right now, don't wear the jersey. Hi-vis yellow is not allowed. Bright colors in general should be avoided, really you should stick to black, white, and dark blue.
Really the best stuff out there is assos if you can afford it. It's easily the best designed stuff in terms of fit and materials. The only reasons I don't wear it everyday are it's lavish cost, and that I'm on a team that I'd like to represent. I fantasize on a regular basis about my team clothing fitting as well as Assos, so if you own a ridiculously expensive bicycle, and aren't on a team, you owe it to yourself to try it out.
Worth mentioning is that jerseys must have sleeves. You aren't a triathlete, you shouldn't have shoulders or biceps, and we shouldn't have to look at them. Do not show up on a group ride in a sleeveless jersey. Ever.
Follow these basics and you'll be fine. Some people out there just don't get it though, so a few more items need to be spelled out:
DON'T BE THE GUY IN FULL KIT OF SOME TEAM YOU AREN'T ON!
Even worse is the guy that gets the bike to match the clothing of the team he isn't on. Nobody believes that you're friends with Dave Zabriskie so don't try to pretend he just happened to give you all of his shit one day. This goes doubly for anything involving USPS, Discovery Channel, Astana 2009, or Radio Shack. See where I'm going with this? Don't be that guy.
Exceptions include: Teams you used to be on, and one of the following: Bottles, Socks, or Gloves associated with some professional team other than those mentioned above.
I feel like that's about good. Stick to basic color coordination, and if all else fails, white is a good choice for your frame, helmet, and/or clothing. Cyclists really like white, so you should take advantage of that.
Next up: LANCE!