How? Use this idea from this great food blog, Chocolate & Zucchini. What Caroline Mignot has done is create attractive monthly calendars for people to use as their desktop background.
Think about this: what is the one thing people stare at up to 40 hours a week or longer? That’s right: their computer! Most people have not so great backgrounds. Make them an attractive one with some message you want to communicate and you will have them thinking about it all the time.