FYI, it's called a CHP here (Concealed Handgun Permit). They use that term specifically so it doesn't include all weapons (like a larger knife or an Asp baton, for example).
As for signs, the only places where it is legally binding is federal buildings (because it's illegal to bring firearms in, signs or not), some buildings in local and state jurisdiction (they must be posted, though).
I believe the only outright OC bans are in Denver and Breckenridge (I've confirmed the first, but not the second - that's only hearsay).
You also cannot bring an openly carried firearms on to the real property of a school (K-12), or within 1000 feet beyond that. When you get your CHP, that will allow you to carry on to the real property, but only in your car, and it must stay in your car if you get out (I leave mine in my car safe when I attend my niece's school plays) - even if you have your CHP, you cannot bring it out of the car. The same goes for U.S. Postal Service - okay for the parking lot, but not into the building.
State-owned colleges are required to allow concealed carry, but most ban open carry. Private colleges are private ground, so their rules apply.
On that matter, private ground means they can kick you out for any reason. If they catch you carrying, while the signs might have no force of law, trespassing laws can still be applied. So if they ask you to leave - do so immediately. Don't argue, don't try to convince them to change their mind. Get off their property and address it from outside or via mail/email/phone if it matters to you (I just tell them I'm not returning with any of my money).
Anyway, those are the usual questions for Colorado carrying. As for the rest, open carrying isn't exactly common, but I regularly do so without issue. I've seen one person caught off guard that I was carrying (she physically reeled back, even though nobody touched her), and one person come up to me to shake my hand because I was openly carrying. Multiple non-interactions with cops, but not all of them are as cool about things as Lakewood PD is.
EDIT: Oh, and uh...Welcome to OCDO.