"And when you offer a sacrifice of thanksgiving to the LORD, offer it of your own free will." (Leviticus 22:29)
My wife has been posting daily notifications on Facebook about things that she is thankful for. I've noticed some others doing this too. Thankfulness is such a great heart attitude to cultivate. It keeps us, at the least, somewhat focused in the right direction.
As we approach Thanksgiving it is a wonderful attitude to hone in on. Look at the word. Thanksgiving is a combination of "thanks" and "giving." Thankfulness is a wonderful healthy heart attitude but it can only truly be done with a sense of giving -- it can't be done grudgingly or forced. It really has to come from within BUT it can be cultivated.
Cultivate it in the small things. Sometimes in the hustle and bustle of life we forget that. Be appreciative of the small things that others do for you. Let them know how grateful you are. Count the blessings that God has given you today. Take some time to express it to Him!