Adjusting sub-categories schema and bullet style


My project home shows categories and sub categories.

A lot of my designated categories have 10-15 sub categories. In short I’d like to:

  1. adjust style of the sub categories to appear more tabular or at least have a fixed width across 3 or 4 lists side by side.

  2. swap some bullets with a font icon (color is key), some with an icon sized png but then some just keep the square bullet.

My question here is which layer(s) should I be editing? There seems to be a number of ways to accomplish these things.