Every walkthrough/guide/faq I've found for FEZ just has the answer to the number cipher, but not the steps you're supposed to take to solve it on your own. How is it intended to be solved?
I wrote an essay (with pictures!) explaining how I think the number cipher is intended to be solved.
Here's the cliff notes:
- Figure out 0-3 from the dimension diagram.
- Figure out the set of symbols for 1-8 from the boiler room, although you don't know which ones are which.
- See that 3 is not in the boiler room symbols, which means there must be multiple symbols for 3.
- See the formulas in the classroom, and guess what the two horizontal lines mean.
- Notice that overlaying images corresponds to adding numbers.
- Figure out all the numbers, most importantly the all the single-limbs numbers.
And then you know everything. But steps 3-6 kinda have to be done on faith that you're on the right track, because you get no confirmation until the end. That makes this a really hard puzzle.