Here are some ways you can try to soothe or pacify a highly stimulated or agitated dog:

1. Stay calm: Dogs can pick up on your energy and body language, so try to remain calm and avoid getting agitated yourself.

2. Remove the source of stimulation: If your dog is agitated due to a particular object or situation, try to remove it from their sight or move them away from it.

3. Redirect their focus: Give your dog something else to focus on, such as a toy or treat, to redirect their attention away from what's causing their agitation.

4. Use calming techniques: Try using calming techniques such as massage, aromatherapy, or music therapy to help soothe your dog.

5. Provide a safe space: Create a safe and quiet space for your dog to retreat to, such as a crate or a designated area in your home where they can feel secure and calm.

6. Consider professional help: If your dog's agitation or stimulation is persistent or severe, consider seeking help from a professional dog trainer or veterinarian who can provide guidance and support.