>Guided visualization can be as simple as closing your eyes while watching a Youtube video. Any type of video you're comfortable with really, but in our case, we do best with video game let's plays. As an example, we are intimately familiar with Super Mario 64, and are a big fan of the Game Grumps, and their playthrough of it. Crude language warning, if you decide to watch them. Earlier I spent 40 minutes 'watching' the first three episodes, except I had my eyes closed. Just based on the game's sounds, and sometimes the grumps' reactions, I visualized what I thought was going on in my mind the entire time. Sometimes I opened my eyes for a moment just to check what was actually going on, and understandably was off by a bit. But there's nothing wrong with that, all that matters is that you're practicing visualization! You can almost forget you're even doing it for practice and treat it like a game, for fun. You may want to find a less chatty let's player if you have trouble filtering out their conversations though.
>Or you know, don't even watch a let's player. I would say the possibilities for this are pretty much endless. For video games, it may help to actually be familiar with the game you're trying to imagine (though I suppose you could also try it blind). But for anything dealing more with "real life", all you need is your imagination. You probably won't be visualizing what's actually going on very accurately, but again, that's not the goal. If you want to be more accurate, open your eyes/check the video every so often. It's not cheating, and if you have particularly poor visualization it might help give you something to work with. In the case of video games it'll probably end up being a necessity to stay in the same place as the video, but that's fine.