Here's a longer list that what I originally wrote...
1. "Always carry, never tell."
2. Think ahead of what you will need...and don't buy emotionally...but base it on your shopping list. (I know... I know... it less fun that way...but you will save $$$)
3. So...what do you need: a pocket gun, an IWB gun, a full size gun that will also function as your house gun. (You'll have to decide if you want to go with revolvers or pistols.) You really need to think about this...otherwise, you will end up with duplicates: LCP and Kahr .380; j-frame and PM9; 1911 and.... you get the picture.
Since the OP was asking about CCW guns, I wont mention the much important pump shotgun, .22 rifle, AK or AR, etc.
4. Invest in a good gun belt and holster. Yes, always use a holster, even when pocket carrying.
5. Did you know that a small piece of cloth stuffed over your pocket holster can really make that distinctive gun outline disappear from your front pocket. (Make sure that it doesn't interfere with the trigger guard!!! Obviously, you want a pocket holster that completely covers the trigger.)
6. Always buy one more box of ammo than you will use in the range.
7. Buy a safe and bolt it down.
8. Don't buy dark jeans. (Buy light blue jeans instead of dark blue jeans.) When you pocket carry and "print"...that "printing" becomes permanently etched in your jeans. You'll know what I'm talking about when the jeans fade around that area.
9. When buying IWB holsters, make sure that there is a "sweat guard"...so that the pistol does not directly touch your skin.
10. Oh...when IWB carrying...also wear a belt...even if your are a skinny guy and can get away with IWB carry without a belt. Wear a belt. (If you leave your fly open by accident and suddenly your front waist button becomes unfastened...not only will your barn be completely open....but your carry gun will come tumbling down the floor. This is embarrassing...especially if it happens in the mall.) (Don't ask....)
11. Yes...I said buy quality holsters... but the most expensive ones are not always the correct one for YOU. My $12 IWB holster works better than my $70 IWB holster.
12. And don't skip quality when buying guns. Get the best that YOU can afford.
13. Skip the .22 mini revolvers and derringers.
14. For really small pocket guns: LCP, Kahr .380,
15. For slightly larger pocket guns: Kahr PM9, SW 642