Step 1: Gather supplies
The instructions can also be downloaded there, but I found them rather lacking. So that's why I decided to put this instructable together.
Glue: I used both a glue stick (not pictured) and Aleene's Tacky Glue
(I find Tacky Glue much easier to use if I pour some in a plastic tray and use a toothpick to spread it)
Scissors: you can use a pair of regular scissors, but you might also like to use a pair of shorter detail scissors, like those pictured.
Step 2: Cut out the petals
Step 3: Glue and fold petal pieces
Step 4: Cut out each petal
Step 6: Glue tabs together
Step 7: Curl petals
On Part #5 curl both edges of the petal inward with one overlapping the other
On Part #6 and Part #7 curl both edges of the petals loosely inward
On Parts #8 - 14 curl both edges of the petals outward
Step 8: Make rose center
Step 9: Adhere outer petals
Step 11: Cut out and assemble the base (Part #2)
There are two #2 tabs; apply glue to the white area of one of the tabs and fold the other one over it.
Apply glue to the white area of the #2 tab that is now on top and fold the remaining tab down on top of it.
Note - this will be a three dimensional pop-up pyramid type piece. It is not supposed to be flat, so don't squish it down!
Step 12: Adhere roses to base
Step 13: Cut out and adhere leaves
As you can see in the picture, I also glued a ribbon bow to the back of the leaves. I thought this would make it easier to pin it on as a corsage.