Well, first I would do some research on how you want to make your os. You should make a list of all the things you want to incorperate into it.
Second, I would either start making a bootsector or
a kernel. You should check out
www.osdev.com and under OsdevRing there is a list of people making there own os's that could help you. Also goto the links page on the same site and the three major sites you should goto is Operating System Resource Center, Code Your Own Os, and Boda Fide OS Development.
Third, Search some search engines for stuff on creating your own os.
google = lots of linux stuff
yahoo = a couple of sites on os
Aslo, Look through this forum and others for incite on you os. Once you start coding, the forums can help, especially if you can't get your code to work!
If you need any other help, you can always email me at
[email protected]