Sometimes a production manager or a printer will require you to crop your illustration. Crop marks must be defined by a non- rotated rectangle.
Follow these steps to create crop marks:
Draw a rectangle around the area that you wish to define with crop marks.
With the designated rectangle selected, assign no fill and no stroke to the rectangle.
Select Object Crop Area Make.
Figure 22-6 shows crop marks in the document window.
You can convert the crop marks back to a regular rectangle by selecting Object Crop Area Release. Because you use only one set of crop marks in a document, you can replace the assigned crop marks by creating and selecting a new rectangle and assigning crop-mark properties to that shape. The old crop marks will revert to a regular shape. When you print color separations for spot or process printing, the crop marks you set on the artboard define the printed area for separations.