Skills are measured on a ‘scale’ of 3 to 18, although Skill Levels can be less than 3 or more than 18. Normal people aren’t likely to have a skill level of more than seven in a skill unless they’re especially dedicated. Competency is gained at skill level 2, and anyone with a level of 5 should be fairly good. When you create new skills, design them around those levels.
Skills are usually things that directly affect specific panels in a comic book. They are physical or mental actions. Skills require that you train to get better. Studying helps, but it’s not enough.