1. Start by showing your boxer a treat in your closed fist. Allow them to sniff and lick your hand, but do not open it until they stop trying to get the treat.
2. As soon as your dog stops trying to get the treat, say 'leave it' in a firm but calm voice and open your hand to give them a different treat from your other hand.
3. Practice this exercise several times a day, gradually increasing the time your boxer has to wait before receiving the reward.
4. Once your boxer consistently responds to the 'leave it' command with the treat in your hand, you can start practicing with items on the floor. Place a low-value item on the ground and cover it with your hand. When your boxer stops trying to get the item, say 'leave it' and reward them with a treat.
5. Gradually increase the difficulty by using more tempting items and practicing in different environments.
6. Remember to always reward your boxer for obeying the 'leave it' command and be patient and consistent in your training efforts.
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