Colorizing
1. First you open the image you want to colorize, I'm using this.
2. Now that we have our image, we're going to go to Colors>>Colorize or Shift+L
3. Something like this will pop up.
4. Here is a handy color-chart, just move the arrow on the right up and down to get your colors.
Hue Saturation
0-12 255 = Red(s)
12-20 255 = Orange(s)
20-45 255 = Yellow(s)
45-113 255 = Green(s)
113-183 255 = Blue(s)
183-215 255 = Purple(s)
215-235 255 = Pink(s)
240-255 255 = Red(s)
5. Play around until you get the color you want, and voila! Here is my finished image

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