there are good programs which make it really easy to make mods. One of these are "First! Weapon Editor" by Karaffka (short "FWE"). Otherwise can you use any simple text-editor program like Notepad to make your own mod. Do these simple steps:
1. Open "weapons.ini" which you find in Soldat-folder. Read it.
2. Open "weapons121.ini which you find in Soldat-folder. Edit it, and remember to choose
"Save as...", not "Save"! The file should be saved as .ini, like original.
3. Start Soldat and type /loadwep <mod-name>
Example: /loadwep iv_weapons
4. Kill yourself in soldat, example type /kill
5. Try your mod
6. Start over again
and at last you've made your own mod.