Grid colors make unique graph papers!
Initially, all grids are created using the default line palette.
To pick a different default palette color --
 Open a tool on the right-side Toolbar.
 Find the color palette in the tool's menu. The square indicates the selected color. Tap one of the small color circles to change feature to that color.
Below are two screenshots of the Major Grid menu. On the left the grid is green because the 1st palette color tile is selected, and on the right the grid is blue because the 2nd palette color is selected.
Ways to use line colors and weights
 Make a graph paper easier to use by selecting different line weights and colors for each grid division. The screenshots below show the Major Grid with heavier green lines than the fine line weight purple lines of the Minor Grid.
 Set all line weights to fine and pick a different color for each grid division. Below shows Major Grid lines set to a darker shade of green than the greens used for the Minor Grid and the Subdivision. Get more detailed instructions on this approach in the blog entry "Create Fine Line grid paper for precise plotting".
Switch to a different palette
To see all the palettes available, tap Palettes icon on the right side tool bar either —
Switch to a predefined palette
Tap Palette on the toolbar and scroll through the palettes. Notice how the grid updates as you scroll — swapping out the original palette color with the new palette's color based on the position of the color tile in the original grid's palette. Below, the left-most (first) color in the Default palette, green, is replaced by the left-most (first) color in the just scrolled-to Blue palette, dark blue. Similarly, the purple from the Default palette is replaced by the lighter blue color.
Leave the picker on a palette to make it the selected palette.
The screenshots below shows some menus updated to the selected palette --
Create a custom palette
1. A good way to start is to open the Palettes tool and scroll to an predefined palette that is the closest to what you want and tap '+ Add' .
2. The Color menu opens. Here you can set the color of each of the four tiles. Tap a color to see its RGB value.
3. As an RGB value is changed, its color tile is updated. There are two ways to change the RGB value --
Optionally, tap in the Name box to edit the default Palette name into one that is meaningful.
TIP: Frustrated setting RGB colors?
Finding RGB values can be frustrating, especially if you are unsure how to 'mix' a particular color. Stuck? Search the internet for a website used by graphic designers that suggests color palettes and helps to find RGB color values.
4. Dismiss the the Color pop-up and your palette is added to Palettes. It will be available to every graph paper.