The-Architect told a fast and easy way which will work very well. He told you all what is important.
Anyway, let me tell my method just to give you ideas. I use a script which contains several possible loadouts for units. If you just have to change the weapon loadout for a single unit, Architect's way is fast, easy and absolutely correct. Whenever you need to change loadout for more units with different loadout settings, maybe my way could help.
; loadout.sqs
; *****************************************************
; ** [this, "LAWSoldier"] exec "loadout.sqs"
; *****************************************************
_unit = _this select 0
_loadout = _this select 1
removeallweapons _unit
; jump to selected loadout
goto _loadout
#LAWSoldier
_unit addMagazine "M16"
_unit addMagazine "M16"
_unit addMagazine "M16"
_unit addMagazine "M16"
_unit addWeapon "M16"
_unit addMagazine "LAWLauncher"
_unit addMagazine "LAWLauncher"
_unit addMagazine "LAWLauncher"
_unit addWeapon "LAWLauncher"
exit
#Officer
_unit addMagazine "G36Amag"
_unit addMagazine "G36Amag"
_unit addMagazine "G36Amag"
_unit addMagazine "G36Amag"
_unit AddWeapon "G36A"
_unit addMagazine "SmokeShell"
_unit addMagazine "SmokeShell"
_unit addMagazine "HandGrenade"
_unit addMagazine "HandGrenade"
_unit addMagazine "HandGrenade"
_unit addMagazine "HandGrenade"
_unit addWeapon "Binocular"
exit
; continue script as you like.....
now in a units init line just insert
[this, "Officer"] exec "loadout.sqs"