It’s time to decorate your blank walls! All you need for this quick DIY from uptodateinteriors.com is washi tape, scissors, a ruler, and a box cutter, this craft won’t cost you much. The first step is to mark where you want your triangles placed. Start from the center of the wall for even placement. Make a mark for the top and bottom points of the triangle. Make sure to press the tape down with your finger to make sure it’s smooth and sticks well. Use a box cutter to cut tape at the ceiling and baseboards. Use scissors for other cuts if you are working in smaller sections. Voila, you are done!