Starting Set

Well levelling up a FA at the moment and I'm about around level 70 and was just wondering when should I start caring about gear? I've been reading around and people start caring about their gear at like level 80 and things and I was wondering when should I specifically go for a set and what set to get? I don't know much about stats and don't know the significance of things like 7/24 etc. I plan on making my FA a forcium set one eventually but want to know what I should specifically aim for to filler for that?