1. Make a folder in Soldat\Mods. Call it "s3xybarret". Spaces can't be used in soldat mod titles.
2. Copy the folders that came with the mod (Probably Weapons-gfx, Interface-gfx, and maybe Sounds) into the new folder. So, to find the new ingame barret facing right, go to
"Soldat\Mods\s3xybarret\Weapons-gfx\barret2.bmp".
If the mod comes with a custom weapons.ini, copy that into the s3xybarret folder. (Not in a subfolder, just the s3xybarret folder itself)
3. Open notepad.
4. In notepad, type the following:
soldat.exe -mod s3xybarret
5. Press Ctrl-S.
6. In the "Save as Type:" thing, put "All Files".
7. As the file name, put "sexxaybarret.bat".
8. Save in the main \Soldat\ folder.
9. Close notepad, and start "Soldat\sexxaybarret.bat".
10. Dance while Soldat loads.
11. Test ze mod.
12. If it worked, DANCE AGAIN!
13. If not, see if you did everything I said right. If the problem persists, (yay I sound like Microsoft!) see if anyone else has a way.
I hope this helps.