One of my students has made lots of snowflakes including this very cool one by clicking the pair of scissors and snipping off parts of a triangle just like with a piece of paper.
Once you think you are done, click on Preview Flake to see what it looks like. Then you can cut some more, or choose SAVE My Flake. You are asked for your name (which means you agree to this website terms of service), and then click SUBMIT. The site will generate a unique snowflake number for viewing in the gallery.