First you need to train the cue leave it, you can follow the tutorial below. Then when your dog understands the cue you can start adding the difficulty of being off leash passing and leaving food items on the floor. The tip is using the plastic fruit and veggie containers you have around the house before recycling them.
COMLPETE LEAVE IT TUTORIAL: https://www.youtube.com/watch?v=Re66qOiso28
Here is a video tutorial on how to train your dog to leave trash that’s on the ground out and about: https://www.youtube.com/watch?v=PLuKnrVYmQs
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