Sulky Training
Once you have a dog who happily walks in front of you pulling the tires and responds to the reins and verbal commands, it is time to introduce the sulky.
First let the dog sniff and explore the sulky. Hide a few treats on it, around it, under it. Once there is no apprehension of the sulky, go for a walk with the dog and the sulky. The dog walks while you pull the sulk. Make it a fun walk or several walks. Go on different surfaces so the tires make different sounds. If treats make the walk more fun, OK. Mostly just going for the walk is fun enough.
Second, hitch the sulky to the dog. Go for a walk on a smooth level surface. Walk until you know the dog is fine with pulling the empty sulky. The next day you may want to walk behind the sulky using the reins to guide the dog. Take the sulky on various surfaces such as gravel and grass.
At this point the dog is fine with pulling the empty sulky. Add some weight to the seat. Go again. Add weight until it matches your weight.
Finally you can ask a friend to guide the dog with a leash while you sit in the sulky holding the reins. If the dog steps out confidently you can tell the dog to wait, have the friend undo the leash and then tell the dog to pull. Off you go. Keep it short, fun and easy the first few times.
Add distance as the dog gets stronger. You are on your way to having a driving dog.

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