How to create a two triangle pattern in Adobe Photoshop tutorial
As with all the tutorials on this site, there are probably an infinite number of ways of going about creating a triangle pattern in Photoshop (see an example below of one possible result) and of course, an infinite number of possible triangle patterns - this is just one way and one style
1) select the rectangle tool
2) go to the settings at the top of the page
3) set the option to fixed - so it matches the dimensions of the document. So if your document is 600 x 600 then set the fixed size for the shape to 600 x 600.
4) Set the option to layer
5) set the color to whatever (red, green etc).
Now, you can use the rectangle tool to drag a shape to the 0px and 0px in the document (always would love to see an option in the settings to set the initial point for the left / top etc but sadly that appears not to exist in PS).
Anyway, once you have the layer in the top corner drop the layer / release. You can find many different triangle and triangular themed brush strokes for use in PSP and Photoshop etc
1) The next step is to duplicate the existing layer and that is done via the layer and duplicate layer menu command or via the layer panel.
Now you have two layers.
2) Select the delete anchor point tool via the toolbox (beneath the pen tool depending on the customization of the Photoshop toolbar).
3) Go to the bottom right corner of one of the top layer and remove the point (a dialog will pop saying that the shape will be turned into a regular shape, say ok).
Now you will have a square and a triangle.
1) Go to the layer panel
2) Select the rectangular tool
3) select the fill option in the top bar of Photoshop
4) and set the new color for the triangle. You can set it to any color, perhaps if using red for the first then you can set it to a lighter red or perhaps a darker red or check out combinations via the extension 'Adobe color themes' so an inverted color etc.
Now you have two colorful triangles
1) Now go to the layer menu
2) flatten the layers (bottom of the menu)
3) go to the edit menu and define pattern command.
4) You can now use the triangle pattern via the fill command as well as new layer fill content etc
5) Set scaling to 25% etc in the fill layer content panel
Of course, you can also re-color the triangle pattern (two combination) and define that as a pattern in Photoshop
1) Flatten two triangle pattern
2) go to the image menu
4) Hue and saturation
5) Change hue setting
6) Edit menu
7) define pattern
8) layer menu new fill layer content etc
You can set the color in countless combinations.
Or duplicate the two triangle layer and then scale say to 75% and then define that and so on or duplicate the two triangle pattern layer and then scale and rotate and perhaps use an adjustment to re-color the duplicated layer and so on
Or perhaps warp the duplicated layer or apply effects and so on.
Or add additional paths such as a circle to the triangle pattern and then define that as on the right.
You can find other tutorials on the patterns such as how to copy the colorful (as well as black and white) Photoshop patterns to other applications such as PSP and Affinity Photo and how to create a pyramid shaded pattern in Photoshop and how to create a color square grid pattern but filled with random colors in Photoshop tutorial