Popsugar Living Harry Potter DIY Harry Potter Mug What Better Way to Enjoy Your Afternoon Tea Than With an Adorable DIY Harry Potter Mug? August 7, 2016 by Kelly Ladd View On One Page Photo 8 of 10 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 8 Step 7 To set the drawing, place the mug in a preheated 350°F oven for 30 minutes. Let it cool before you touch it. Previous Next Start Slideshow Harry PotterDIY