Look for new colorful WorldCat banners at your library
You may have already seen a few new posters or bookmarks at your library. Simple and color-saturated, if you're really dedicated you can download a desktop background and show your library support all on your own!
If you live in town and want to do some "guerilla marketing" on behalf of your library, you can print off the posters or ads, for example, and hang them in bus shelter stops, at coffee shops and other community gathering places. It's all free, fun and brings a breath of fresh air to promoting WorldCat in person.