I am always surprised how often I get asked about cleaning. How often, how to...
First, read your owner's manual. Yes, I know the ladies did, but the guys need to as well. It will tell you how to field strip your gun, what to look for, how much oil to use (yes, they are not all the same, some like to be mostly dry and some like to be basted like a turkey).
ALWAYS use eye protection, ensure that ammo is no where in the area and where protective gloves. Use a bore cleaner and a lubricant, two separate products. Use a shot glass or small glass dish (I use a little Pyrex bowl) that is dedicated for the bore cleaner and stays with your cleaning kit. Pour bore cleaner in it, and when you are done, toss the remainder, this means you are not contaminating fresh cleaner.
As for how often? I've never heard of a malfunction caused by a gun being too clean!
I may not clean my Glocks every time I shoot it, but I do clean my .22s every time. Get to know your guns. There is great satisfaction to be had in knowing how to field strip, clean and reassemble your own firearms. You can see the wear, you can see if things look right. If you have trouble, consult a knowledgeable shooter, instructor, or Range Officer for help. Never try to force the parts, they should come apart fairly easily and go back together easily. If not, double check the owner manual, or someone experienced with your model of gun. When got my first Glock, I was a little mystified by the take down lever until someone showed me...then...EASY!