A big stamp like this three ferns wood-mounted rubber stamp from Hero Arts can be used on a CAS card...if you limit the space it takes up with a mask. Add a big sentiment, and you're golden.
Or teal, as it were.
Mercy, grace, peace, and love,
stamps: Hero Arts, Papertrey
ink: Hero Arts ocean, intense black
paper: Papertrey white
accessories: silver metallic marker (Prismacolor), ruler, post-its for mask, metallic shimmer enamel dots