I had a real hard time getting this achievement mainly because the description is not the best and other guides have missed important parts of this.
This is exactly how I got it:
Go to FREE DRAW and either open your existing drawing or start a new one.
1. Start with the 'Draw Tool' and draw a little line with every different tool.
2. With the Finger Paint picked, go and change to every single color and draw a little line. Make sure that you are choosing all 8 colors and also the sub colors which I have listed:
Yellow + 4 Sub Colors
Purple + 4 Sub Colors
Orange + 4 Sub Colors
Blue + 4 Sub Colors
Red + 4 Sub Colors
Green + 4 Sub Colors
White + 4 Sub Colors
I would suggest to double check and re-do the colors in case you did accidentally picked another one. What I did to make sure is selected each of the colors twice!
Once this is done, in case the achievement does not pop just like for me when I tried this several times, do the following.
3. Use all of the Draw Tools again and draw a little line with each of them with the last one being the Crayon.
4. Pick the eraser and choose both of the erasers available to erase a little off the screen.
5. With the Crayon, draw all 6 Shapes. Size does not matter; however, don't put them on top of the lines that you have drawn since you will need at least one of them for step 6.
6. Use the Fill option to fill in one of the shapes that you drew. I filled in my box and the achievement popped!