I recommend visiting the trendy, cool custom cards sites - like Tiny Prints and Wedding Paper Divas - and finding a design you love. There are plenty of places to be inspired by good design. You don't have to come up with that on your own. When you find something that appeals to you, go to StoryBook Creator and make it even better - make it your own!
Thought I would share a couple things I did this month...
Front of Hannah's Baby Thank You Notes. Insert photo boxes around the edges. Drop and drag the photos into place. Add text. Voila.
The back side allows room for the thank you note!
Kiley's wedding thank you notes. I used the same basic idea because it is what I love right now.
On the back side I bled their names edge to edge and lightened the opacity so they could write right over their names. I think it will make writing their hundreds of thank you notes more fun - ha.