As always, carrying a concealed handgun is a huge responsibility and one that should not be taken lightly. Learn and know your states laws that govern ccw so you won't make a minor mistake that could become a major problem.
Stay alert. I have found that while walking across a parking lot at the mall or a department store (at night or during the day) I can keep a better level of awareness of my surroundings by actually counting the people that are also walking to or from the store / mall. I make it a point to make eye contact with people in my daily travels. This has the effect of letting the ones who may be up to no good know that I have seen them. I know they are there, I know what they look like. I have seen people who looked to me like they were sizing me up for one reason or another actually look away and shift their direction of travel after I made eye contact with them.
Be aware of what you do with your hands. I have seen guys I know are carrying in Wal-Mart and Target. I know they are carrying because I watched them subconsciously touch their gun, or I caught a glimpse of the gun when they raised their outer cover garment while reaching for their wallet. I watched one fellow get out of his car then pull his pants up by placing his hand on the bottom of his OWB holster and what I assume was his spare mag(s) on the opposite side of his belt, through his cover garment, and pull his whole belt/holster/mags rig up in the same manner I have seen LEO's do with their duty rig. To me, that was a dead give away. Maybe he was an off duty LEO, maybe not. Either way, I knew he had a gun on and if any half way street smart bad guy saw it, they would too. Don't give yourself away, surprise is your biggest asset.
Avoid using the urinal at a public restroom. Standing there at the urinal puts you in a perfect position for a disarming attempt. If the bad guy saw you do something that gave away the fact that you were carrying, he might just follow you to the restroom and wait 20 or 30 seconds and then come in after you. If you are at the urinal, you are trapped, most times on 3 sides. Standing there, you are the perfect mark to be disarmed.
Carry a cell phone with you. These things can be a pain because everyone can get in contact with you but, it also means you can contact the police, EMT, who ever needs contacting when things go south. Also, think about keeping it on vibrate only. If for some reason you are hiding from a bad guy or a group of them, this is when you phone will ring the loudest. Murphy is still alive and well.
Carry a flashlight. I carry a small high output white L.E.D. light with me at all times. It is made by Coast Cuttlery and it’s the Tachtorch model. So what if it is day time hours? Ever been in a big store or mall and the power went out? A tunnel with no power? An underground parking garage? Who of us knows every day exactly where we are going to be called on to go in our daily lives? It might save your life.
Don't feel bad if you realize in the next few months that the gun you bought for your first ccw is way to large or heavy for comfortable daily carry. Most of us went through the same thing. My first ccw was a full size Taurus PT-92. I still have it. I look at it now and I wonder how the heck I ever carried that big, heavy thing every day. It's huge. What was I thinking? Who knows but I now carry a MUCH smaller gun.
Don't get into arguments over stupid things with morons. No road rage. No arguments over a parking space or other trivial matter. It is your duty to not escalate any situation. Remember, in any confrontation between you any anyone else, there is at least one gun present, yours. Don't get into a fist fight while armed. This increases the chance your gun will be knocked out of its holster and into the hands of your possible murderer. If you get knocked out you are now susceptible to having your gun taken away from you and used on you or someone else. Walk away from idiots who want to fight.
As a side note to the no fighting, don't hang out with people who like to fight or cause trouble. They will drag you into their fights and you may be held legally responsible and loose your ccw rights or worse. Not only that but if they know you carry, it might actually embolden the fools to mouth off to larger fools because they will figure you have their back since you have a gun. Don’t hang out with people you wouldn’t feel comfortable having watch your children.
Avoid large crowds with drunks or rowdy people. This kind of goes along with the above advice. Mobs and crowds often make collectively bad decisions and you can be dragged along into the stupidity. Don't let that happen to you.
Lastly (this is long enough I think...sorry) Don't save your money to buy your dream gun and then carry it in a $14.99 nylon holster. Would you spend $40,000 on a car and then put $20.00 Wal-Mart tires on it? Buy a good quality holster such as a Don Hume, Galco, FIST, CompTac, Blackhawk or others. Blackhawk makes some very good holsters.