First, I just draw the outline of the sunflower. Then, add midtones and different shadows into it. Because I feel a little bit hard to use the mouse draw on the computer. So I did my task 1 on iPad illustrator. Which is easier for me by using an apple pencil. And then I upload them into the computer for task 2.

In task 2, I first chose very light yellow colors that were just like the sunflower's original color. And I also made an optical illusion which is very cold and blue. 

Here are some examples that I experiment frames, shapes...

I did tried making some watercolor texture although I didn't use it in final scarf. 

I really like the texture that dry brush give to me.

In Task 3, I selected a photo that I took last year for the background. 

Clipping Mask, copy and paste and then add effects.

And I also tried to use the watercolor texture, which looks not too bad. 

I created a green frame that fits the background. Adding shapes, circles and sunflowers. I also repeat a pattern to make the shape in the center. And now, everything is almost done.