A gunslinger gets 4 + Intelligence modifier skill ranks per level. Since you have a -1 Int modifier, you get 3 ranks per level. The human gets you another per level, bringing you up to 4. You also get a Favored Class bonus, which can give you either an extra hit point or skill point per level. If you use it for skill ranks, that would bring you up to 5 per level, so 10 total.