There is nothing wrong with overclocking on the asus a320m-km or any other quality made motherboard. It's just that hard core overclockers want to take CPUs to their bleeding edge and it might not the right choice for that. If you want to do a mild overclock and the system stays stable, then great ... enjoy.
I understand you bought 3000 MHz RAM ... a fine choice. In BIOS, you would select one of the XMP profiles (there might be more than one, depending on your memory) to run the RAM at 3000. Your motherboard literature refers to this as an overclock because the memory controller (which is on the CPU) will have to be overclocked (BIOS will take care of it for you) and they will not guarantee it will work. Avoiding "burning up" your system is all about heat management. Good case ventilation and a decent CPU cooler should do the trick, but the best thing is to monitor CPU temperatures. They should be around 35 C at idle and under 80 ish when working hard. These are really guidelines becuase the reported temperature are approximate (+/- 5C normally). If temperatures are fine, but the system is not stable (crash, bluescreen, errors, etc), then you may need to be less aggressive.