Gray Matter
It is an open question whether or not a prospective applicant for a job should dye his gray hair. On the one hand, it would give him a youthful appearance. Perhaps he would appear to be a more energetic person.
Lo Yilbash
Men Dyeing Gray Hair in the Gemara
Whether a man may dye his gray hair to look younger for a job or a shidduch, given the prohibition on adopting women's ways of beautifying themselves.