Method, procedure (5,8)
I believe the answer is:
modus operandi
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">method</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I have seen 'Method of working' mean 'modus operandi' so perhaps 'method' could also mean 'modus operandi')</span><br/ ><br/ >'<span class="explanation-format__original">procedure</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(modus operandi is a kind of procedure)</span><br/ ><br/ ></span>
(Other definitions for modus operandi that I've seen before include "Method of working" , "MO in full" , "this shows how it's done" , "Habitual procedure" , "Particular way of doing something (Latin)" .)