[header] How to add molding to cabinets [title] Measure the length of crown molding you will need. [step] Begin by using a tape measure to determine the total length of your cabinet tops. This will determine the total length of crown molding you need to purchase. 
If this is your first time working with molding, consider buying about 20 percent more length than you need to allow for mistakes and wasted material. [title] Construct a guide fence for use with your miter saw.