First and foremost: You must know ho to work MS Paint, The GIMP, Photo Shop or anyother program you might be using.
Now, you need to know some more: How to define your own custom colors instead of just the basic two shades of every color. This is Hex. a Six Character Code, each letter defining some color bit. The code digits that are used range from: 0-9 & A-F, defining custom colors isn't as easy as it sounds, well, making up your own I mean, defining them is as simple as drinking water!
Here are the easiest Hex Codes:
Black: #000000
White: #FFFFFF
Red: #FF0000
Blue: #0000FF
Green: #00FF00
Yellow: #FFFF00
Grey: #DDDDDD
You open up the color mixer and mix away! Aha! Wait a minute though: MS Paint wont show you the Hex Color Code, it shows you the RGB Color Code, lets get to know our friend RGB: RGB, a.k.a.: Red Green Blue. Most things like RMXP when picking the color of a Screen Flash uses the RGB esque system, of a meter with: Red, Green and Blue, to define your color. Also, let the truth be told, there is also more stuff!
Lets meet our friends! Sat, Hue and Lum: Nice, very nice, and easy to know too!
Lets go over what each of these three defining codes do:
Hue: On a scale from 0-239, the hue defines the first angle of RGB, we will talk more about those is a minute. Just remember that Hue is the first angle. (Not the best way to learn it, but ok, none the less, I'll explain more further on)
Sat: On a scale from 0-239, the sat difines the second angle of RGB, after the Lum part, we'll get to more of this stuff!
Lum: On a scale from 0-239, the sat defines the light of a color, Now, we get to the heart of RGB!
If hue defines the first angle, WAIT! Slow down here, what is the first angle anyway?!?!?!
Ok, think of it as a scale from zero to eight: 0 1 2 3 4 5 6 7 8
0Red 2Yellow 4Bl/grn 6Prple 8Red
1Orange 3Green 5Blue 7Pink
Get it? 0 Hue is Like normal. Also, Hue goes from left to Right, the more Hue, the farther right, the less Hue, the farther left. (Horizontal)
Now, if you didn't know what hue was, than you might not know what Sat is. But if you do, skip this.
Ok, Sat is like Hue, only it goes Vertical, so, because there are not enough colors, lets just say this:
The less sat: the more grey and then black, the more sat: the more color and more light.
So, if you have your color to dead on red: the less sat, which you can only go down, will make it darker. Interesting. Not at all.
Get it? No?!?!?! Ok, here's more:
Say, if you want a nice ice blue, leave everything the same and put it on a blue, but lower the sat and lower the angle vertical wise.
If you are still confused or just don't get it, wikipedia it.
Lum: Now, every color so far is defined by Hue and Sat (RGB wise). Ok, but I hear you talking about this thing called Lum. What is it?
Lum is for further defining colors, see the side bar with the lever esque thing that you can raise and lower, that's lum. It defines the colors light. Lum I assume standing for Luminescent, like lights. Or something a long those lines!
Got it? Ok, I'll explain more!
If the Lum is set to 239, no matter what the color is, it'll be white, yet if the Lum is set to 0, it'll be black, and in between those, are a wide range of colors. Just check it out for your self.
Now that you have that down, time to dig into the fun stuff!