flower

Use a piece of watercolor paper, tape it to a board.
Prepare a few color washes.
Draw a flower outline with a wash.

Color inside the outline.

Lift some color in the top part of the flower.
stem

While the flower is still wet, continue painting the stem with a different color.
Have the colors bleed.

Add another color to the stem.
shadows

I like to use darker colors and blue to add shadows to an object.
Grab a small amount of blue and add it to the bottom part of the flower and the areas that logically would be in a shade.

While all colors are still wet, you can add another color to the flower.
leaf

Start the leaf with drawing the outline and filling it in with a color wash.

You can add another color to the leaf while it is still wet.

When the first layer is dry - apply a darker wash to a leaf half.

When all previous washes are dry - start drawing "between the veins" shapes.
Leave gaps between those shapes - they will become veins.

Continue on both sides.
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