Well, first you need some kind of image editing software. I use Photoshop, but you can get demo versions of Paintshop Pro that will do a great job.
http://www.jascsoftware.com/ Now, once you have an image editor, the first thing to do is to start with a gunsight that is close to what you want. There are some already in the Aces High\Sights directory for you to play with, or hit HTC's web site and there is a gallery of many gunsights you can download. Open one of these up with the image editing software. As long as you want to work in the same color, you should be able to select a paintbrush and then either the primary or secondary color and edit away. If you need to put down the pink color, use the dropper tool to suck it up as your right-click color. It will work best if you use the magnifying glass tool to blow it up first and work a pixel at a time by setting your brush size to 1.
Now the trick is that the file is a bitmap that is in indexed color. If you want to change the color, you will need to change it's mode to RGB color make your changes, and then set it back to indexed color. You will likely need to "flatten" the image if you edit it as well, before you can save it as a bitmap. In Photoshop this is done from the layers menu... I'm not sure about PsP.
It's really quick and easy once you learn a bit about the editor you use. Give it a try and if you have any troubles ask away.
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Lephturn - Chief Trainer
A member of The Flying Pigs
http://www.flyingpigs.com "A pig is a jolly companion, Boar, sow, barrow, or gilt --
A pig is a pal, who'll boost your morale, Though mountains may topple and tilt.
When they've blackballed, bamboozled, and burned you, When they've turned on you, Tory and Whig,
Though you may be thrown over by Tabby and Rover, You'll never go wrong with a pig, a pig,
You'll never go wrong with a pig!" -- Thomas Pynchon, "Gravity's Rainbow"