So, you want an awesome guild insignia, but think that square of white just looks a little sucky?
Here's how to fix it.
remember the guild insignia requirements: must be in .bmp format, must be in the dimensions 32 x 32 pixels
take your image, in this example, I'll be using
open the image in an image editing program, for the sake of ease, I have chosen to use MSpaint in my example.
Select the "Fill with colour" tool (aka the paint bucket)
Add a new custom colour to your palette, with the exact numbers as have been highlighted in the red box
Fill any area you wish to make transparent with this colour.
Make sure to save as .bmp format.
You can now go to your guild interface and select "Test Insignia" to see exactly what your insignia will look like in game, the example below is the test display of this image
I hate the pink outline... how do I get rid of it?
or you go to edit the emblem, zoom in, fill paint the background some safe color (like green if you don't have any green in the emblem), you will see some pixels remaining pink -- they are what gives the pink outline because they are not the proper color due to blending. use the droper and sample one of these tiles, fill paint the safe color area with this sample, then re-fill paint it the safe color. Find the next off-color pixel and repeat. Continue to do this until you get rid of all the non-transparent pink shades.
Doing it this way you can keep any lighting/shading effects on the edges that tend to get lost when using other methods, aswell as smoothing out edges that sometimes get jagged from the blending that are noticable when the background blends are taken out.