During the manufacturing process there might be 1 mm shift. If your design contains any images or background that extends beyond the final size of the product and that is where the bleeds are important. Bleeds are there to make sure if there is a slight shift during manufacturing, that there won’t be a white stripe at the edge. In order to create bleeds – just extend your elements beyond the design. The minimum bleed requirement is 0.1” at each side. So if you are designing 3.5” x 2.0” business card with bleeds, then your file page size should be 3.7” x 2.2”.
Make sure to have all of your essential content elements like logo, text and images slightly inside the design. Safe zone is the area with 0.15” from each side of the cutting area. If your content is too close to the edge of the design then it might be cut off during production.