SD cardstock in crimson is THE perfect red for Valentine's cards. I love using a bit of SD Rouge to break monotony. The white and black help your designs 'pop'. And this year I found Lady Pattern paper in red to offer an interesting background.
Pure simplicity in the first card. The card base in white is matted with black SD black and then with SD crimson. The lattice heart was made using an electronic cutting file from Birds Cards on my KNK Zing. The label in SD rouge stands out against the crimson background. The sentiment is part of a Creative Dies Christmas set.
The Tattered Lace Florentine heart adds a really romantic touch. This is further enhanced with part of the Butterfly Magic die that comes with TTL magazine issue 20.
Lady pattern paper in script red pop creates an interesting, contrasting background for the intricate electronic cut heart (from Silhouette Studio). the printed paper is also used on teh last card.