Oh, I've been creating a lot of tech content, like my old days on Reddit. These days I mostly lurk on LGTQ subreddits though and idk how the Lemmy community feels about that (not that I have much to post in that regards anyways, link/forum wise)
Yeah, I've started just posting anything that seems interesting while trying not to flood the place. I'm pretty deep into the tech world so it's been mostly tech, but I'd highly recommend posting content that interests you and I'm sure it'll interest others.
If you're using a lemmy web interface (as opposed to an app), there is a cross-post button you can use to post in other communities that are tanginately related (if you decide to create a community for your topics).
/r/buildapc and /r/buildapcforme. Has been helpful to get a general idea of what parts to get and feedback on if the build is balanced for what the user intends.
/r/buildapcsales, /r/gamedeals, /r/consoledeals are other ones. There's sites like isthereanydeals and pcpartpicker, but those subs have come in helpful for catching deals I would have missed.