Well, I'm afraid you're not going to get there unless you're going to scrape sulfur from the mouth of a live volcano and figure out a way to turn that into thiosulfate. Whatever you're going to do, you'll end up being reliant on the chemical industry one way or another.
For rapid fixer, the 'best' you can do is either a sodium thiosulfate-based rapid fixer that exploits the 'trick' of adding ammonium ions in the form of e.g. ammonium chloride, or starting with ammonium thiosulfate either as a concentrated solution (typically 60%) or solid crystals. The latter are slightly problematic to work with as they tend to decompose, and a fixer made with amm. thiosulfate crystals tends to end up being very cloudy with some elemental sulfur floating around in it. This can be filtered out, but it adds another process step (and filtration is kind of slow to begin with).
I've made quite a lot of fixer myself, rapid and otherwise, and I've never found it to be a particularly smart way of working. If you use pool-grade sodium thiosulfate, it is cheap, yes, especially if you can also find a cheap source of ammonium chloride. You still end up doing work that is realistically speaking unnecessary given the good availability and manageable cost of ready-made rapid fixer. I can imagine this is perhaps not the case in same parts of the world and I don't know what the present supply situation is in Iran, so maybe that could be part of the rationale of going for a DIY fixer.
Anyway, a rapid fixer is really as simple as chucking some ammonium thiosulfate into water. If you start with sodium thiosulfate, then use that and some ammonium chloride. The quantities actually aren't very critical; a couple of heaping spoonfuls of thiosulfate per liter is a good starting point; maybe one or two heaping spoonfuls of sodium chloride. If you mix it right before use, you don't have to worry about adding any sulfite either as it won't have time to go bad anyway. If you want to store your fixer for a while, add a few spoonfuls of sulfite (preferably ammonium, but sodium is cheaper).
There are plenty of formulas on the net and also on Photrio that will give 'exact' grams etc. But as said, it's not critical. Do a clip test before using your fixer and base your fixing time on the clearing time you observe.