Here's a card DIY for a super easy and super cheap (wont cost you a thing). Using things you can find in your desk.

Step 1: Things You Need

Things you need:

1. A piece of plain white paper
2. Color markers, color pencil or crayons
3. A pencil
4. An eraser
5. Scissor or a cutter knife

Step 2: Fold 'em

Fold the paper into 1/4 size.

Meaning for the 2 times.

Step 3: Draw 'em

Draw a simple stencil on the front side of the paper. The idea is to make something easy for you to cut out.
I draw a cupcake for mine, but here's other ideas for you to draw:
- star
- heart
- flower
- music note
etc

Step 4: Cut 'em

Start cutting the inside of your drawing. Well, stencil style..

Step 5: Color 'em

Color the inside part of the card, the second layer of the front part.
you can either put abstract colors (go crazy) or color it accordingly to the cut out drawing (like mine)

Step 6: End Result.. Taadaa!

Don't forget to write the inside of the card.
You could also color the front part of the card. I zazzle my card with gazillion rainbow dots and a hint of sparkle.