Open a new raster layer, 500 x 500 pixels or the size you want and with your Preset Shape Tool set at rounded rectangle draw out a card shape the size you want (foreground off, background colour set to white). Objects – Align – Center in Canvas. Convert to raster. Click the card with your magic wand to select and fill with a colour, texture or pattern of your choice.
Draw a heart, either using a preset shape or a dingbat font, size depending on your card, using a colour of your liking. I used a dingbat font, with the colour set to red. Place your heart in the left upper corner and add a slight drop shadow. Layers – Duplicate, then Image – Mirror and Image – Flip so you have the heart in the lower right corner. Close off you card layer, and merge the two heart layers, then open the card layer again. You can find a card symbol font at http://www.pagat.com/com/cardsttf.html if you want to use a symbol other than a heart.
Choose a font of your liking, colour of choice and add some text if you wish. Convert to Raster, then Image – Free Rotate, direction Left by 90 degrees (All layers and Rotate single layer around canvas unchecked). Add a slight drop shadow. Layers – Duplicate, then Image – Mirror and Image – Flip.Close off your other layers, and merge the two text layers.
Add an image or photo of choice, or any other embellishments of your choice, meerge visible, and you’re finished! You can also add a slight bevel to your card.