Socializing isn't just dog-to-dog interactions or meet and greets with people. It's exposure to new experiences, objects, and noises that will help to build your dog's confidence in the world around them.
What do I do? Provide distance to an unknown object- this is key when working on impulse control. You'll want to start at a distance in which your dog is comfortable and pair with coaching them through your expectation of how they should act (for example: sit or down). From there you'll want to slowly work your way closer to the unknown object while enforcing your expectation.
What are some socialization ideas?
Observe these from a distance:
The dog park
A construction site
Your local fire Station
A busy street
A busy playground
Anything on wheels (car, bus, bike, skateboard, wheelchair, etc)
Take a visit to a less crowded but dog-friendly:
Parks (Local or National)
Stores (Home Depot, JoAnn's, Petco, TJMaxx, etc)
Sit and listen to:
The vacuum cleaner
Rustling grocery bags
Opening a trash bag
What should I expect? In the beginning, you can expect the practice to be pretty chaotic, but stick to it! You'll start to see your dog's tolerance for being around those scary objects grow to the point that they are ignored!
Coco always enjoys her trips to Home Depot!