This is how i went about it. I already had Zoey trained to sit calmly before she will be given a treat. I left a bag of treats on my enclosed back porch that everyone uses to enter the house. I instructed anyone who was coming to visit to grab a treat before they entered and make sure that it was plainly visable.
When someone would come in she would go to jump but as soon as she saw the treat she would immediately sit waiting to accept her prize for being relaxed. After about a dozen times of doing this I began to leave out the treats and replace it with praise. It worked real well for me. I hope you have the same luck.