Here are two I made yesterday. The first card is really simple. I used my Mini Cricut to cut out the hearts (love that machine - I could just cut things out for hours!). I taped the hearts to white card stock and a red card, added a few shining hearts and stamped the sweetheart sentiment. I like the way the hearts flow.
The second card was almost as easy and quick to make. I found the heart online (free printable) and cut it out. Then I taped the heart on a paper lace doily and added both to a finished card -- the light green stripes printed on the card really go with the stripes in the heart. I wish the colors were truer in the picture. The flowers are more orange than red, but I changed the brightness of the picture so the the doily and heart outline could be seen easier. The final touches were the paper flowers and little roses on the left (purchased at Michael's). Pretty and feminine.
The first card has been entered in the Just Us Girls Challenge: