I need to create cutter guides for a business card insert in a brochure.
I know how to technically create a new layer called cutter guides and use my pen tool to create the lines, but I am inexperienced in understanding where to place the guides, what size they should be, and how to position them accurately.
I know they need to be diagonal cuts across to opposing corners. I don't know how long the cuts should be. The cards are 85mm x 55mm.
Current Method
I draw a square, line it up inside one corner. I guess the size, but usually about 1cm, I rotate it 45 degrees. That gives me my diagonal line (creates a corner).
Then I draw across the diagonal with my pen tool. Then I use alt, ctrl and drag the corner to expand it equally in both directions past the edges of the card, giving another half a cm each side.
Is that a good way of doing it? Is there a better way? Googling it just provided me tutorials on die cut business cards, am I using the wrong terminology?
How can I work out the right size of the cut, and the best position for it?