Greetings.
As Brendan said, the wiki has a goo deal of material about starting points and different things you can try (or try to avoid). You definitely want to read the
Introduction,
Required Knowledge,
How to Ask Questions, and
Beginners' Mistakes pages first thing, if only to get an idea of what's what.
I would definitely recommend starting by getting your tools in order. Before anything else, consider what you want for your target system, development host, emulator or virtualizer, toolchain, language(s), editor, and version control system, and get them set up for what you plan to do. Note that even if you want to use a different language, you should have a good handle on C and the target system's assembly language before you begin, if only because all OS work involves some amount of assembly coding, and most of the information about OS-dev is geared towards working in C. If you are using binutils (the GNU tools used by Linux, and the long-time favorite of most hobbyist OS devs), make sure you have a separate cross-compiler set up for your development work, and get familiar with writing Makefiles (or whatever build tool or project manager you have chosen).
Also, don't even
consider working on a project this size without version control - if you don't have some way of rolling back changes, you will come to regret it. This is true of any larger development project, but doubly so for OS dev. VCS repository hosts like Github, Sourceforge and Bitbucket are usually free for open-source projects, and relatively inexpensive (or free) for private ones, and the effort of using them is trivial, so there's no excuse for not having a cloud repo.
A lot of people, including myself, have started out with writing a bootloader, but it is a lot of work for something that really doesn't move your kernel design forward. My recommendation is to use writing a very simple two-stage bootloader as a warm-up exercise, something to get you into the swing of assembly coding and low-level access, but not to rely on the result unless you are certain that your OS design won't work with an existing production-quality loader (which is very, very unlikely).
Beyond that, it is up to you. I would recommend reading the pages on "
What Order Should I Make Things In", for both inspiration and a bit of a chuckle.
(not much of a name, but if you say MyOS anywhere here we know it is "your" os...)