Always wear protective clothing. Never dump unused mixed pesticide down the storm drain or on the ground. All unused pesticides should be disposed of by absorbing the pesticide in cat litter or other absorbent material. The same procedures should be used for all pesticide containers. Know how many pounds of fertilizer or pesticide per 1000 square feet you are applying.
Most spreaders come with calibration instructions.
Never apply fertilizer or granular pesticides so they fall on pavement. They will be washed into the storm water system and back into ponds and streams. Often a lawn service will provide a blanket spray program for all customers. There are differences in the management techniques for warm season lawns and cool season lawns. Find out which you have and what is being used on your lawn.