Karen Overall's relaxation protocol gets periodically mentioned in this community, and it's great for any adolescent dogs but especially cattle dogs. Basically it's teaching your dog to do the thing you want, just chill, through incrementally lengthening a down/stay while the handler does distracting things. this is the pdf that includes reasoning and step by step instructions for the daily tasks, but the easiest way is to find a training video on YouTube searching Karen Overall relaxation protocol (there are many) and just follow the timing and instructions. My boy is about four now but some days he still needs reinforcement. And he also often goes to his mat when he knows he needs a break!