unique things you can give your characters to make them stand out that are not tattoos or scars:
multiple ear piercings (especially for male characters)
visible body piercings (nose piercing, etc.)
lots of jewelry (layered necklaces, rings on every finger, etc.)
or no jewelry at all (bonus: a character that doesn't wear any in a culture that is jewelry focused)
a signature color (ex. a character that always wears blue, or only wears gold rings)
extra descriptive hair or eye color (ex. curly, red hair down to the waist, amber eyes with flecks of green, cropped silver-blonde hair)
freckles (bonus: body freckles, not just face)
a nervous habit (ex. picking at their skin, biting their nails, checking a watch, fiddling with jewelry)
a limp or any other unusual gait (bonus: describe it! is it from a horseback riding accident, were they born that way, is it from aging, etc.?)
an accent or lisp (use cautiously and with respect)
unique teeth (tooth gaps, missing teeth, gold/silver teeth, crowded teeth, etc.)
a signature hairstyle (a braided coronet, a bun, etc.)
noticeable facial features: ruddy cheeks, a prominent nose, very thin/thick eyebrows, moles, birthmarks, etc.)