How to create a square grid filled with random colors in Photoshop. Create a guide for the squares via the view menu and new guide layout and set a cell size for the random color filled squares. Select the rectangle tool and draw a cell using the snap to option for the guides. Change the color of the squares for the random color filled square grid. Repeat for all the cells. You can also fill the square cells of the random color filled grid with images. You can also use rectangles instead of squares and fill rows and columns of the color grid. The random color filled Photoshop square grid can be re-colored by using adjustment layers and effects to change the color. You can also define the random color filled square grid as a Photoshop pattern via the define pattern command. This tutorial shows you how to create a very colorful random color filled square grid in Photoshop along with a number of variants.
New guide layout and set to 5 x 5 etc
View menu and snap ON and snap to guides
Draw square in cells of the guide layout
Change color via properties to a random color
Repeat for each cell in the square grid
A square grid in this tutorial. One made up of multiple square grids. You can make all kinds of random color grids, of course, such as rectangle or perhaps thin slivers of fills - the approach is much the same. Likewise, the random color grid can be 4 x 4, 200 x 20 or 10 x 30 etc. The basic approach is the same.
Go to the view menu in Photoshop
New guide layout.
Create a basic columns 4 x rows 4 (or 5 x 5 etc) with no gutter etc and you will end up with a nice 4 x 4 set of lines which can be filled.
Set "snap" to ON
Snap to only "guides"
Use squares but it could as easily be rectangles. Also, you don't have to fill each and every square. You can also fill the square and then add an additional stamp (image) or another path etc.
Select the rectangle tool in the Photoshop toolbar
set to shape layer option
Go to the settings along the top option bar and set to square (instead of unconstrained)
New guide layout 6 x 6
view menu snap ON and snap to guides
Set the color for the square via the properties
Repeat this with different colors
In the example on the right, alternate squares were left empty and then filled with an image rotated and flipped in the random filled grid
Go to the view menu
New guide layout
Set columns to 20 and rows to 20
View and snap ON
View and snap to guides ON
Go to the rectangle tool
Shape layer option
Create a rectangle and stretch a number of cells down (keep it only one cell wide or one cell deep)
Go to the properties panel (window / properties) and change color
Create another rectangle
Change color via properties
Repeat and fill the design
The design can be added to and changed indefinitely. The key thing is to test out the pattern (if you want it as a repeating pattern) and also just to check for any colors that just don't see right (such as the long blue line that stands out in my image)
You can set the color to any color - best select via the swatches (but it is your choice). If you want the colors to be different in each square of the Photoshop pattern then make certain you set different colors to the one above, left, right etc
Also remember to do the same for the cells to the left of the left and to the right of right etc which should avoid matching the left to right and right to the left and top to bottom etc
Set to shape layer option
Set color to blue via properties
Apply another square
Set color to green via properties etc
Check that no blues are connected to other blues etc
Go to the edit menu and define pattern command.
Add the fill via the edit menu command or the layer menu new fill content or via the layer styles etc
Edit menu in Photoshop
New fill layer
Set pattern to new random color grid
You can re-color the random color grid in Photoshop by using adjustments such as color filter / hue and saturation etc and the results will still be pattern (sometimes perhaps better than the original).
You can also use the Adobe color themes to help set up a nice color scheme for your grid. You can also add additional paths on top of the artwork.
The one on the right is the same as the random color grid above but via the hue and saturation adjustment and saturation reduced.
You can duplicate the artwork and then scale the grid by 50% and then use blending modes via the layer panel to combine them to create ever more interesting tiles for use in PS. You can also use the results of any of the experiments as a possible brush via the edit menu define brush command (though the result will be grayscale).
Or save the result to a PSD file and then use the artwork as a source for displacement maps
Or you can just warp the resulting fill and random color grid layer
Create random color grid
Layer menu in Photoshop
New adjustment layer
Hue & Saturation
Change adjustment via properties for layer
I have been mentioning Photoshop patterns but the same artworks can be used in Affinity Designer etc just by saving the item as a PNG and loading that via the various pattern / bitmap features in those apps.