Make a flyer with your pet's description, name, the specific date and time lost, and place last seen. Include a clear photograph of your pet, in color if possible. If you don't have a good photo of your pet, take one today, just in case, and take a new photo every few years as your pet ages. Consider offering a reward that is large enough to be an incentive to a thief or good Samaritan to return the animal safely to you. Call area schools, particularly grade schools or middle schools, and ask if you can distribute posters and reward information among the children.
Kids spend a lot of time outdoors and are often the finders of lost pets.
Personally check for your lost animal. We cannot overstress how important it is that you go personally to these places. Go back to them every other day. Do not call them or rely on the shelter personnel to find your animal for you. Notify the police.