You can just copy the code from existing article if you're making one on the same category (weapons, characters, maps, etc...). Otherwise everything else follows a standard wikia format, there's no special format here. If anything goes wrong, other staff will help finetune the article for you.
TristanBladeB wrote: You can copy the code (in Source Mode) from the similar weapon's article. E.g: GG-Halloween. to make GG-Noble Silver. Therefore, info such as manufacturer or ammo count,.. can be similar.