1.) Pick your topic, in this case, it'll be some sort of famous person. (For ex: Mozart, Abraham, Churchill, Ceaser, Harrison Ford, etc) But make sure to pick the person you feel is important, or feel a connection to.
2.) Traditionally, Ode's are kind of long, but I the Ode your writing can be about three to five stanzas.
3.) If you want to make it rhyme, good for you. If you don't want to make it rhyme, that's fine as well.
4.) Thesaurus. You might use a word several times, so making sure you have replacements might be a good idea.