I am about to put a photo in a frame and have bought a 'photo mount card'. You know the sort that fits the frame and borders the photo by a couple of inches. How can I cut the hole out at the 45 degree angle so as to show the white inner of the coloured card. I have a multitude of sharp modelling/craft knives and straight edges, but don't know how to acheive the required angle. I hope I have explained myself OK but if you need clarification, go look at a picture on your wall and all will become apparent.
Thanks
John