How do I create a font dds file?

Edit: This forum is behaving really weird, don't know what happened to the original post, this was posted as a comment.... Anyway:

I have managed to create the file now. Using Intels dds plugin https://software.intel.com/en-us/articles/intel-texture-works-plugin
Turns out the fonts are BC3, not BC7.

But there's a new problem. Absolutely nothing happens when I replace the bigblue_1.dds and bigblue_2.dds files (the colored pixels). However changing bigblue_0.dds makes a difference to the regular characters. It is as if they are saved somewhere else. What's going on there?

Edit: Scratch that. Turns out that the colored pixels are a lot bigger than what is actually used by the font. So just reducing the size of all the tiles until they fit solved it.

Now the question is, how to turn this into a mod?

Edit: Scratch that too. Turns out this was the easiest part.
My advice is, open up someone else's mod and look inside. Especially, take a note of the structure. Then go into the space engineers installation folder. You'll find the same structure. In other words, there's your template.

Mods are in C:\Users\<username>\AppData\Roaming\SpaceEngineers\Mods
Game files are in wherever you install your steam games > steamapps\common\SpaceEngineers\Content