custom sounds help

[ThaGreatOne]

well ive been trying to follow dark metals custom sounds tut and it makes no sence. the cut/copy/paste thing doesnt work for me. when i paste the sound... it just makes a new thing it doesnt over write it. (is that what its supose to do??) and when i "cut" something it just gets rid of it. even though i put it in the middle of my sound. its confusing and i just dont understand it