I sorta have an outline system. Basically I just start jotting down plot points, events and details. And for different branches Ill note if they lead to death, an ending, or converge back in.
Sometimes I name sections as ChapterA1 or C3, and sometimes use asterisks and stuff for other notes. Im sure there are better ways to do it but it always makes sense to me when I go back and look at it...usually.
Imagine a tree's roots and a gardener. Some gardeners prefer to keep their tree's splitting segments in a preplanned pattern, fanatically ensuring that every single story path in meticulously manicured; Some gardeners prefer to allow their tree's roots to sporadically sprout, shooting out and spreading across the soil, barely paying attention to where the paths are taking them.
Both approaches to cyoa writting have their downfalls and advantages.
If you try to ensure everything is rigidly rooted in a preplan you can lose some of the fun in writing and slowly stop investing time into the product. If you let the project develop itself in any way you choose: the absoloute weight of writting you'll have to do will drag you down. My advice? Have a preplan: but if you see an enticing oppurtunity to add a fun looking path, don't restrict yourself.
Good luck on your duel with Zombie, if thats still happening.
Well... I'd say it is about finding what works for you. However you can obviously learn or take inspiration from others, so might as well share my thoughts. Do keep in mind I haven't actually finished any storygames, not properly at least, so take this with a grain of salt.
The popular word processor, I know at least one other person who uses it to plan their stories out. It can work, but you sort of need to figure out a way to keep track of things as it is designed for linear stuff. You can go the folders route where you utilise your computer's capabilities, or you can add headings and stuff (numbers too probably) and keep it all in one document. I use the later method, but it seems to get a bit worse when the branching gets heavy, but it really depends on the style of branching the story is using.
Major downside is this one costs money, but free alternatives exist, and you can technically use Notepad... but I wouldn't recommend it. This one sorta depends on what computer you have, I use Windows (like a newb), so if you don't you'll be looking at different names for similar products.
Being able to see the squares and lines is nice, but Twine doesn't seem the best for this if you are doing anything more complicated than just branching on each choice. Heck, even then, if I recall correctly, zooming out a lot means you'll only be able to see the titles, which might not be enough.
twinery.org link, for those who wish to check it out.
Playing around with this atm, and it is like Twine but better, as I can colour the squares, make them other shapes, and have more 'visible' text. It seems pretty good, so if you like the visualisation of branching, you might want to consider finding a flowchart program and see if it fits what you're looking for.
draw.io is a browser based one that I stumbled upon (by googling, didn't look hard), so I guess it has my recommendation, but many others undoubtedly exist as well.
You can use a pencil if you want. Anyway, this method offers the most flexibility as you can literally draw anything. Granted, most people can't draw well (tho I'd say they could probably learn), however just making squares and connecting them with lines is doable. The limitations of the page you are jotting it down on are also not wholly negative, as it can help keep the story from spiraling out of control (even more so considering the strain of writing!). Granted, this depends on how much you write (as writing tends to be slower than typing), and your handwriting size as well.
I still advise getting a piece of paper because being able to write some things down can be really helpful, and it doesn't even require a computer! I have plenty of empty writing books around, so this method is rather accessible to me. Using printing paper would work, but can become annoying if you end up with many separate pages, in which case figure out some organisational method.
I worry this method might get overlooked when there is so much quality computer stuff to use instead, but mixing and matching is a valid option for covering weakness, and paper has stood the test of time quite well.
Or something... it is a software that is either free or had a free version, and it was made for planning books. I used it to back up one storygame, and it seemed pretty neat. It had stuff like 'chapters' and 'scenes', and scenes had characters, setting, etc. You could also make items, and they could be ticked as 'present in scene' (or something).
However, other software also exists, I believe Scrivener is popular with some accomplished writers here, and I think that one has a free trial or crappier free version. The reason I used YWriter was because I heard how good Scrivener was and that if you used it you couldn't use the worse ones... I didn't want to be locked out of options! Anyhow, if you have money definitely worth at least looking into it a little, but keep in mind that the goal with outlining is to write the actual story at some stage, and not just outline forever.
Spreadsheet software! Using it to make square maps is fun. Anyone this is similar to Word, so I should have put it up top. Anyhow I think you are likely better of using a flowchart software, as it scratches a similar itch, but I figured I should at least mention it.
There is undoubtedly much more options, and I haven't even mentioned the actual methodology for outlining, but I'll leave that for when I actually finish something. I will say that unguided writing (or very spares planning where you go scene to scene) can be good if you just want to start writing and getting something out there. It is about finding what works for you, but I would say that giving this a go can help you better understand what will produce best results for you by broadening our horizons. Some planning (or perhaps strong revision) does seem to go a long way, but enough rambling.
How do I outline? With software or paper! Experiment to find what works for you, there really isn't a wrong answer, but looking at what others are doing can provide some invaluable guidance. Also, keep the scope of your story in mind, as you can always have it spiral out of control, regardless of what software/paperware you use.
P.S. If you think of something, write it down. Most people have a phone, if you don't maybe get a small book. The thing with inspiration is that you can forget it, and that sucks, a lot. So being able to jot down some things (or type it into a phone app) can be invaluable if an idea strikes when you are not sitting at a computer. I think this also encourages your brain to give creative farts, as it realises that you are remembering what it released... tho to phrase it a little bit better, habits are a big deal, and building a habit of creative freedom can be good.