how to do better color changing?

i took a series of images and wanted to change the default color, but i suck at cs6/photo editing period.

the background was mostly green, the name was blue, and the robot guy had green glow instead of red.

note that minarix looks like it has spudged brush strokes, but or some reason on my end it doesn't only when i try to take a picture of it.

links to orginal content.
http://wallmii.com/wp-content/uploads/2013/04/Nvidia-Green-Logo-Full-HD-Wallpaper.jpg
http://us.download.nvidia.com/downl...DIA_GeForce/gearup-desktop-bkgd-1920x1080.jpg

 

Adjusting colour in your image is a very important technique in graphics, and there are many ways to go about it.
To begin, click Image>Adjustments in photoshop. These some of the tools you may use to adjust your lighting and colour to suit your project.

[Beginner]
The first method I recommend, is Colour Balance. This allows you to control how much you want to saturate a particular colour in a certain area. To do this, slide the bars to get the effect you want. You may also change the depth of lighting you want to change. Eg. Shadows, midtones, and highlights.
I suggest using this technique in later stages of colour correction.

The next method of adjusting colour, is using the Hue and Saturation tool. This is by far the most basic way of changing an image/layer's colour. To do this, simply drag the slider until you get the desired colour. You may also change how saturated the colour adjustment is. This determines if the colour is vibrant, or dull. -100 being black and white, +100 being maximum saturation (not recommended).

Another way to change a specific layer's colour, is with layer styles. This is achieved by double clicking the layer you wish to alter. This will bring up the layer styles menu. Once here, click the option 'Colour Overlay'. Don't panic, the layer will become fully embedded with red. Next, change the blending option on the colour overlay to either 'Hue' or 'Colour'. This should make the layer visable again, only this time, all colour in the layer should be red. To change the overlay from red, simply click the red box, and it will open up a colour palette for you. You may also decrease the opacity on the overlay for a softer change.

[Advanced]
Yet another method of changing colour, is using Gradient maps. These are quite hard to use at first, but once mastered, can produce amazing effects. Personally, this is my favoured tool to adjust colours. To find this tool, click the half black/half white circle button, next to the New Layer button (layers tab).
Click Gradient map. Then click the gradient, and change the colours accordingly. Next, change the blending mode of your gradient map to either Hue, or Colour. Because the gradient map is a layer, you can also adjust it's opacity, to reduce the impact of the effect.

This method is quite strange to a newcomer, but it's definitely worth a go.
The tool you will use is called Replace Colour. It is very similar to the commonly used 'Hue/Saturation' tool. The only difference is, you can be very precise and selective when change the hue of a colour in your image/layer.
When you click this tool, a box will appear, and your cursor will be replaced with the eyedropper tool. Using this eyedropper, click the colour you wish to change (you may have to zoom in to be accurate). Then, as you would with the hue/saturation tool, adjust the sliders until you get the desired outcome. Note: if the results aren't accurate, click the +eyedropper tool, this will allow you to adjust more than one variant of a colour, eg. Lime green, forest green, instead of just plain green.

Hope this helped mate sorry that is was so longwinded.
There are plenty of methods out there i'm sure, but these are just the main ones I use.
Good luck!

 

i'll give some of those a try, the method i used was hue, color adjustments, and color burn.