Setting the blades is more hazardous than difficult, since the blades can slice your fingers while handling them. And that’s where a jig comes into play. You must set all blades the same height – roughly 1/8″ . The actual height is not as important as getting them all the same – some planers are 1/8″, a few are e 3/16″. You could fabricate a jig yourself. The purpose of the jig is to set the blade height at 1/8″ and hold the blade in place (without cutting your fingers off) until you can tighten the set screws down. The best option however is to buy a jig. They are magnetic blocks that set the blade height and hold the blade in position. They are about 2.5″ by 6″ in size. For a 24″ planer you need three (3).
 
They run about $69.00 each and you can get them online. The nomenclature is Woodstock International G1755 Planer Pal® – Standard Each