I don't really get the skill system in this game. How do I get more jobs and how do I get more skills? They just tend to pop up randomly.

If you played FF9, it's basically like that. You equip an item that has abilities, you keep that item on and fight. You will then append the ability to your character.

As for more jobs, you run into them as you meet the requirements for them... sometimes they just pop up later in the story (Like you would get the things you need for Mog Knight but you don't see it on the list until later)

Yup.

One thing though, that I find annoying, is equipping characters. It always displays that gigantic list of every weapon EVER. Is there no way of just displaying the weapons available for a certain job? Cos I swear, it's a pain. Some bad game design. :( Still a good game, though. <3

If you change something in the options then you can make it so the list of weapons which comes up when equipping stuff is limited to the items you can equip, excluding the ones you cant. Getting new jobs depends on the moves you know for other jobs. Eg, you get a new job if you learn 5 black a magic and 3 white magic with a human (elementalist job). That should help. Man i love this game.
CHEEEEEEEEEEEEEESE