This is a nicely flexible style, because you get to select the mustache that suits you, plus the stubble length you want. And if you're busy, it doesn't take long to redefine your mustache lines - after which you can just let the stubble grow another day. What's not to like?
1. Comb your beard and mustache neatly downwards.
2. Decide what kind of mustache you want, and define its outline with a precision shaver attachment.
3. Trim the rest of your beard down to light or heavy stubble. Optional: shave your cheeks and neckline for a more maintained look.
4. Tidy up hairs around the mustache outline.
5. To define the shape of your mustache, apply mustache wax or pomade.