Step 1. Create a New Document with 500px x 500px Artboard Setup. Select RGB color for Color Mode.
Step 2. Select the Polygon Tool. Click once at the artboard and enter Radius: 70, Sides: 10.
Just fill it with black color first with no stroke.
Step 3. Go to Effect > Distort and Transform > Pucker and Bloat. Enter 50 and OK.
Step 4. Go to Effect > Distort and Transform >Roughen. Enter Size: 10, Relative, Detail: 0 and Points: Smooth. Press OK. You'll get something like this:
Step 5. Apply a green Radial Gradient (F9) on it as below:
Click the left slider and set Location: 50. It's done for the first layer of our petals.
Step 6. Click on Polygon Tool once again. Enter Radius: 50, Sides: 15. Go to Effect > Distort and Transform > Pucker and Bloat. Enter 100 and OK.
You'll get something like below:
The Gradient effect will be automatically applied on it. Change the left slider Location: 30.
Then go to Effect > Distort and Transform > Tweak. Enter Horizontal: 10, Vertical: 10, Relative, Anchor Points: Unchecked, "In" Control Points: Checked and "Out" Control Points: Checked. Click Preview to know how its look and click OK.
Place our second petals in front of the first one:
Step 7. Repeat Step 6 to create the next petals. Enter these values.
Polygon Tool, Radius: 30, Sides: 15.
Pucker and Bloat: 100 and
Tweak, Horizontal: 20, Vertical: 20, Relative, Anchor Points: Unchecked, "In" Control Points: Checked and "Out" Control Points: Checked. Click OK.
Set the Gradient left slider Location: 15.
And place it in front of our second petals.
Step 8. Ok, the last one. Select the Ellipse Tool or just press L. Click once on the artboard and enter Width: 40px, Height: 40px and click OK.
Then go to Effect > Distort and Transform > Zig Zag. Enter Size: 15, Absolute, Ridges per segment: 20 and Points: Smooth.
After that, go to Effect > Distort and Transform > Roughen. Enter Size: 5, Relative, Detail: 5 and Points: Corner.
Set its Gradient left slider Location: 20.
And place it in front of our third petals. Select all petals, go Object > Group.
Done for the flower.
Step 9. Select the Rounded Rectangle Tool. Click once on the artboard and enter Width: 300px, Height: 250px and Radius: 20.
Fill it with white color with no stroke.
Go to Effect > Stylize > Drop Shadow. Enter X Offset: 1px, Y Offset: 1px, leave everything as default as click OK.
Step 10. Right click the Rounded Rectangle > Arrange > Send to Back or just press Ctrl+Shift+[.
Place our flower to the bottom-left of the rectangle. Make the duplicate of our flower. Resize to make it bigger. Press Shift key while resizing it. Then, set Transparency (Shift+F10): Multiply and Opacity: 30.
Make another three or five duplicates and resize it to make it smaller. Place it on the top-right and bottom-right or anywhere that suits you.
Our final result:
The flower with some other color settings:
I hope you guys enjoy this tutorial and that's all for today. Yeahh!!!
More Vector Graphics: 
