FicWad

They are an alien race of strong physical appearance very similar to that of humans, with the exception of having a more muscular body build and a monkey tail being its weakest point (in the upper-class warriors this weakness disappears). Often they have black hair, although there have been rare occasions that have also been seen with brown hair, blue and blond in the anime series.
The hair of a pure Saiyan is unchanged from the day of his birth, however, it is clear that may fall. This is not the case of mestizos as Saiyan Gohan, Trunks and Goten, exhibiting different hair lengths and with different styles throughout the series.
The facial hair of men blooded Saiyan can grow. Examples include Nappa, Vegeta, and Paragus all have been seen with mustaches, while King Vegeta himself had beard. While Saiyans can grow a beard, apparently, it takes a long time, as seen in Dragon Ball Super when Goku and Vegeta spent three years in the room of Time however, only grew them enough facial hair to cover their faces .
All pure Saiyan seem to have dark eyes, while mestizos do not always share this trait as the son of Vegeta, Trunks and her daughter Bra, have iris blue.

Saiyans, at least in adulthood, are resistant to extreme temperatures, far more than humans, as evidenced by Bardock, flying into outer space to address Freezer last time, Broly survived being frozen in a glacier, and Goku training with increased and against the minions of Slug gravity when using a machine to make the Earth's climate to fall to very low thermal levels.
Personality Edit
They are extremely proud beings since they only believe in force and be greater than any race that inhabit the universe. Saiyans also seem to believe that death is preferable compared to live with the shame of losing to someone inferior to them in level, this especially evident with Vegeta and his main motivation for his rivalry with Goku.