Tropical Transparency Effect
Draw Your Petal
First Turn on your grid View > Show Grid or (Command/Ctrl + Quotes). Then turn on snap to grid View > Snap to Grid or by holding down all three (Shift + Command/Ctrl + Quotes). Set your Fill to None (Forward Slash) and your Stroke to 1px with a Color of Black. Now grab the Pen Tool (P) and draw one half of your petal. Then select that half and go to Object > Transform > Reflect. Make sure its set to a Vertical Axis, a 90 Degree Angle, and hit Copy.
With the arrow key nudge the copy over until the top and bottom points align. You can turn off your grid now View > Hide Grid or (Command/Ctrl + Quotes). Use the Direct Selection Tool (A) and draw a box around the two top points. Then go to Object > Path > Join or (Command/Ctrl + J). For the Points choose Corner. Then repeat the process for the bottom two points. Now your first Petal is Complete.
Turn Your Petal into a Flower
Now with your petal selected with the Select Tool (V) grab the Rotate Tool (R). Hold down (Option) and click on the bottom tip of the petal. This is how you can activate the rotate dialogue box and rotate an object from a point you indicate. Now input a 30 Degrees Angle and hit Copy.
(Command/Ctrl + D) is a really handy shortcut, it will repeat the step you just did. Hit (Command/Ctrl + D) 10 times in order to completely rotate copies of your petals until you have a complete flower shape.
Let's Add Some Color
Select your flower and turn your stroke off. Then set the Fill to a Gradient of your choice. I used a blue linear gradient.
Now to get a more interesting effect go to the Transparency Window and choose Multiply.
Transform Your Flower Into a Whole Bouquet
I didn't want my flowers to multiply each other in the Bouquet. So I copied a flower, dropped it behind (Command/Ctrl + B), turned off Multiply by setting it back to Normal in the Transparency Window, and set the Fill Color to White. Then I grouped this background with the top colored layer. This gives each flower a white background. So their transparencies wont effect each other.
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