How do i let folk's know about a missing dog?

if it has a microchip you can contact the chip company and report your dog missing you can also contact any local or surrounding shelters and let them know to keep a look out for your missing dog.

Post on social media, ask for local rescues to post as well

Put fliers out around the neighborhood, police station, fire station, and at the animal control building. If it's found and sent here they will scan for chip and if none available hopefully look at the pictures.