Here is a video of Marlo encountering a deer on my driveway the other day. We have put lots of work into the idea that the best response to suddenly-appearing prey animals is to turn back to me, even without a verbal cue.
There are many excellent dog trainers working with force-free, proactive methods for helping distracted dogs and I learn all I can. Probably the most influential source I have drawn upon recently is Denise Fenzi and her methods for working with obedience dogs. Pet dogs can absolutely benefit from these techniques as well, and, recognizing this, Denise has published a book called "Beyond the Backyard: Train Your Dog to Listen Anytime, Anywhere!". This book is awesome for pet dog owners and has also led to the creation of Beyond the Backyard classes all over the world.
1) Control the Environment or Control Your Dog
When you're teaching your dog to cope appropriately with distractions, you *have* to practice. When you practice, you need to set up or find distractions, but your dog can't have the opportunity to self reward, or you're just practicing teaching your dog to ignore you. Have your distraction inaccessible, such as a cookie in a sealed container or in a hand. Or, have your dog on a leash so they can't help themselves. In the real world where you have less ability to control the distractions, the leash is the unsung hero. Use it! I promise you can still have fun with your dog.
2) Don't Be Upset That You're Not as Exciting As A Squirrel
Some dog training advice says that you have to work full time to be the *most* exciting thing in your dog's life. This is exhausting. And I promise that for a lot of dogs, there are things in the world that are just more exciting than you (at that moment). Let your dog look at things (if they are scared or aggressive, only from a safe distance), and let them figure out that turning to you is the best response, and will pay off big time!
3) Give Your Dog Time to Process and to Think
One thing that I have had clients comment on that they found unique about my classes is how I teach them to respond to their dog being distracted or if their dog doesn't respond to them right away. If a dog is too interested or distracted by their environment, our tendency is to nag them by repeating our cues over and over again, or to bribe them by showing them food (or if you're a correction trainer, to apply something unpleasant to get them to "pay attention).
There are certainly some instances where I will use food to get or keep attention, but for a dog who is just checking out sights and smells, you are better off to just stand still and wait. When they are ready, they'll check in with you, and then you can make a big fuss and begin your training. And yes, with a young or distractable dog, you might repeat this process a lot. But it gets easier as your dog learns that a) they *can* explore if they need to and b) playing with you is super fun.
After all, what's the alternative, really?