Iris folding refers to a technique where folded strips of colored or patterned paper are layered in a spiral pattern behind an aperture. It is called Iris Folding because it resembles the iris of a camera.
There are several free iris folding templates on the Iris Folding Templates page.
Step 1
Using a craft knife and template, cut out an aperture in the colored cardstock.
If you want to cut a fancy border, now is the time
to do that too.
Step 2
Position the card with the aperture cut-out over one of the iris folding templates, face down. You will be working on the back side of the card.
Tape the card to the template using non-permanent tape (Masking tape works well for this. If the tape is too sticky, stick it to a cotton cloth first to reduce its stickiness)
Step 3
Arrange your folded strips of paper in the order that you want to apply them to the card.
Start with #1 on the template:
Step 4
Using the next color, follow the same instructions for #2. Repeat all the way around the aperture, following the numbers and working inward as you complete each round. Stop when you have the desired size for the aperture opening.

Step 5
To finish the center attach a piece of holographic paper, a small picture, a decorative button, etc. You can now mount your finished work using glue or double-sided tape. 3D Foam pads works well if you used a heavier weight paper for your design and you find that it is too thick to mount directly onto the card.