If it's a C++ function, I would think it'd be name-mangled to indicate the types of its args. See the man page for the c++filt command. Or post the mangled C++ name so someone else can run c++filt on it.
Beyond that, step one would probably be to learn assembly language. Without that, you're not really in a position to do anything else. After all, if you can't understand assembly language, then reverse engineering from assembly language seems to be precluded.
Step two might be looking at the callers of the function you want, and figuring out what gets pushed on the stack or into arg-passing registers.
I'm assuming this is a private or undocumented function, otherwise an obvious Step zero would be to look in the headers. Even a private framework may have headers.
An alternative for Step one would be to find a decompiler for whatever assembly language your code is in, but they tend to not be both free and good, although I could be wrong.