Rather than creating the normal boring cards, why not add glow in the dark tape to them? That's what I've done here.

Step 1: Materials and Starting

For this the following items will be useful:

Glow in the dark tape;
Craft knife or scissors;
Printer;
Card;
Stencil or be good at art.

Once you have these items of the items you are comfortable with. Roll out a piece of glow in the dark tape turn it upside down and draw your shape - I've used a stencil for this.

Step 2: Cutting Your Shapes

Now that you have the drawn picture on the back of your tape you can now cut the shapes out with either a craft knife or scissors.

Next you can place these down on a surface to see how they will look.

Step 3: Creating Your Card

This is the really simple stage. Fo this I simply searched on Google Images for backgrounds that would suit my glow in the dark boat, loaded my printer with glossy card and printed the image to cover half of the card (because it will be folded in half to make a gift card).

Step 4: Transform Your Card to a Glow in the Dark Card

After you have folded the card in half all you need to do now is stick the pieces of glow in the dark tape to the card to make the shape and write your greeting on the inside.