The idea behind this poster was the use of elements from the periodic table of elements. The first circle represented the smallest of the three, which was Lithium, the second Sodium, and the third Potassium. To show this we are going to use electrons. To start we are going to add circles inside each.

Create one circle, and duplicate it three times in the smallest. To duplicate, right click on the new circle layer we created and click on “Duplicate Layer”

Then group these layers together like we did before in a group called “electrons” so we can come back later if needed.

This is what how your new folders and layers should be organized.

And your poster should look like this so far.

Create 11 more circles in the second circle, and create 19 in the last circle. What you should have now is something like this.

Now that we have the circles finished off. We're going to make it more like neutrons by adding some negative bars inside all of the circles.

To start, let's change our primary color to a nice orange. We're going to use the color #FF9900

To start, let's use our rectangle tool to create a rectangles about this size. Make sure you organizer these rectangles in a folder in you layers as well.

Duplicate this layer over and over to fill all the circles. Your outcome so far should look like this