Firstly, we need to adjust the levels; So Layer > New Adjustment Layer > Levels.
Rather than manipulating the layers together as RGB, we’ll do them one at a time to create the desired effect.
Here are the settings I’ve used for each and a small picture of the result at that stage.
In the layers window – Right click on the original picture layer and select Duplicate. Then move this above the levels adjustment layer
Now – with the duplicate layer selected, Ctrl + U to open the Hue/Saturation controls. Increase saturation to around 55-65 to accentuate the colours.
