In My Resume, what are the rules for

Hello. i'm not much of a writer, actually i never write so i'm not sure and more over the Resume is a different beast.. what are the rules for capitalization in resumes??

Anyone know? What exactly do i capitalize and what do i dont.
I know if they start the sentence i would capitalize the first letter but what if these somewhat important terms are within the sentence.

examples are:
-Macos X or macos x . Windows XP or windows sp( Operation system)
-Scanning Project Assistant or scanning project assistant( Job title)
-Document Control or document control or Document control.
Office support or Office Support or office support
-Supervisor or supervisor( as in Communicated with Supervisor)
-Administration Department or administration department.

etc etc

Thanks for reading. I'm 28 year old male but not a writer, and i haven't really done resumes that much. i've gotten jobs through temp agency where resumes were not really needed or were created by the temp agency