I used Authentique paper from a couple of Valentine years ago 'cuz they are terrific colors for the holidays and hearts work all year long. I thought the cardstock would be too bulky but it worked beautifully. I did go over my folds with a bone folder. Be careful with some cardstock as the edges will crack and in that case, just use your fingers to fold all edges.
If you make this project, accuracy in folding is key as well as starting the folding process along the 9-7/8" edge!!! I'm not sure Kristina emphasized that fact in her video.
As I was finishing the holder, I also thought that a belly band would be adorbs for this project also. Stay tuned next week for another sample!