Create OS Extend from FreeBSD
 

I seriously want to know that if you want to create a new os that somehow extends from any *nix-like-os, what are the step process you might know?
Such as ...
- You must create the ASSEMBLY CODE yourself to distibute your os and install it in other computer or not.
- How do you develope your os software? Is it developed on other *nix you extended from and just make then you got execute file?
- And if you dont want to extend from any os. How could you create your own OS.

These questions are just the things I thought about.
Any suggestions?

It would certainly depend on what exactly you're wanting to do.

If you're really interested in OS design from the metal up, this is the wrong place to ask. The subject is huge. So much bigger than can be discussed on this. I've personally read a couple thousand pages (in books specific to the topic of OS design) and feel that I have a very "basic" understanding. I could probably do it but it would be trial and error for a lot of it. I remember changing a major thing in MicroBSD once and how many redundant steps it took. And even the reading hadn't fully prepared me for that process. I understood it when I ran into it but the experience itself was needed to really get it.