To morph into everyone's favourite Snapchat filter for Halloween, start by outlining the base of your nose (so the tip of your nose and an outer oval around it) with a light concealer, like MAC's Pro Longwear Concealer in NC15 (£19.50). Line that area with a white liner pencil, such as MAC Cosmetics Chromagraphic in Pure White, £15. Next, outline this area with your black liquid liner. Use the liquid liner to shade in your nostrils, leaving the very tip white. Add brown shadow for dimension on the tip of the nose (near the nostrils).
Using the liquid liner, make small black dots to mimic where the dog's whiskers would be. Top off with a clear gloss and doggy ears, and you're set!