Punch 9 hearts out of DSP; cut second piece of same DSP for card front.
Cut a piece of white CS to a suitable size for the card front to mount the 9 hearts to. Arrange the 9 hearts then use a piece of press-and-seal to pick them up; apply adhesive to the back of the hearts, then position over the white piece of CS and adhere them.
Adhere the card front DSP to the card front. Adhere the white CS piece (with the hearts) to the card front.
Use Misti to stamp the sentiment.