Icons made using this tutorial:

Open your image. Duplicate it twice. You’ll have three layers called Background, Background Copy and Background Copy 2. Remove visibilty from Copy and Copy 2. (Click the eye next to the layer)

Select the Background layer. Click on the Create a new fill or adjustment layer button and select Hue/Saturation or go to the top toolbar click on Layer-> New Adjustment Layer-> Hue/Saturation.

In the window that’ll pop-up make sure Colorize and Preview are selected [bottom right]. Adjust the colors to the one you like best. I used Hue: 234 and Saturation: 25.

You should only have two visible layers [ Background and Hue/Saturation one]. Right-click any of them and click merge visible. Now turn off the visibilty for that layer. Riht now, none should be visible. After that, turn visibility one for Background Copy. Select the rectangular marquee tool. Select a piece of the image.

Click delete. You should now only see the part you left unselected and black and white checkerboard since nothing else is visible. Now click on the Create a new fill or adjustment layer button and select Hue/Saturation or go to the top toolbar click on Layer-> New Adjustment Layer-> Hue/Saturation. Once again, in the window that’ll pop-up make sure Colorize and Preview are selected [bottom right]. Adjust the colors to the one you like best. I used Hue: -138 and Saturation: 26.

Once again, right-click background copy or the new hue/saturation layer and click on merge visible. Turn visibilty off of that layer and on for the Background Copy 2. Select a piece with the rectangular marquee tool and delete. Remember to leave space for all the colors to be visible.

Cick on the Create a new fill or adjustment layer button and select Hue/Saturation. Once again, in the window that’ll pop-up make sure Colorize and Preview are selected [bottom right]. Adjust the colors to the one you like best. I used Hue: –55 and Saturation: 69 Click OK. Right-click one of those two layers and click on ‘merge visible’. Turn visibilty on all 3 layers and done!