Are we talking a build guide? Or something similar to the Community Game Guide? Or something like Heavy’s Basic Loot Filter guide?
Though, there are certain forum post editing limitations that you’re likely to come across if you need to continuously alter your guide.
There’s also a ton of stuff off-site like a; Wiki on Neoseeker, Wiki on Gamepedia, Wiki in French, Crafting Guide, and I’m sure there’s a lot more out there.
A lot of people post photos here using Imgur.com and Youtube for videos, but I’ve seen several other photo and/or video platforms work as well.