A guided exercise to find the you who is genuinely thankful

Sometimes it's hard to feel thankful on cue. You might know that mindful gratitude is a wonderful attitude that leads to all kinds of benefits. It does, but how do you get there? For many people, thanksgiving holidays are a reminder that they are alone, or that their families are nuts, or that they have way too much to do. You might be stressed or insecure or tired. What's the best way to put all that aside and notice that you are already thankful? What's the best way to get from grumpy to glad?