to slip. also, if a plastic ruler is used the knife can easily cut into its straight edge, damaging it. great care must be taken when using a craft knife as they are very sharp, if they slip they can cut hands and fingers very badly.
4. the net / development (package) is folded. a good tip is to place a ruler on each line and fold the card. the use of a ruler ensures that the fold is along the line. the net can be glued together so that it takes on the form of the package.
1. design a simple package for a product of your choice. draw the net 