Begin by opening up any photo in Photoshop, but keep in mind that photos with isolated objects with a simple background work best.
Next, well de-saturate the image which will be helpful when we being painting the photo. In the Layers palette, click on the half white half black circle button and choose Hue/Saturation.
In the Hue/Saturation tool, set the Saturation to -100 then click OK
Now we'll create a new layer. This is the layer where we will be painting the colors on. Click on the button in the Layers palette that resembles a page turning. This will create a new layer called "Layer 1".
Change the blending mode of Layer 1 to Color .
The primary colors that we'll be using are yellow, magenta, and cyan. Before we start painting, we'll use the Swatches palette so that we can quickly select those three colors. In the Swatches palette (Window > Swatches), click on the drop down icon then choose one of the PANTONE CMYK swatches.
When it asks if you want to replace or append the swatch, choose replace. Your swatch palette will now have yellow, magenta, and cyan as the first three colors. Now you can select one of these three colors quickly.
Begin by selecting either yellow, magenta, or cyan from the Swatches palette and painting anywhere in the image with a large brush size. You can adjust the brush size by right clicking your mouse. Adjust your colors and paint the rest of the image.