Seriously, it is very easy! All you need are these four basic materials:
Step 1: Paper
Start with a square piece of paper. Fold this into a triangle by folding in half once. Next, fold this triangle in half to form a smaller triangle.
Step 2: Cutting
Begin to cut three slits in your triangle starting at the hypotenuse edge. Make sure the folded edge remains uncut and at the furthermost leg of your triangle. (The vertical side of what forms the right angle)
Step 3: Opening and Taping
Unfold your triangle. Starting from the inside at the square, bend the pieces of paper to form what looks like a canoli and tape. Flip your paper over and to do the same to the next strips. Continue flipping and taping until now strips remain. Repeat these three steps until you have a total of six.
Step 4: Stapling and Viola!
Now that you have all six pieces, gather them all together at the ends and staple. Once stapled, let them fan out and staple at the piece that forms a cross to the one next to it at the piece that forms a cross. Do this to each of the individual papers. This step stabilizes the snowflakes form. One finished, viola! You have made your 3D snowflake!