Herobrine is something of an enigma in Minecraft, as his character doesn’t technically exist. In un-modded versions of Minecraft, Herobrine is nowhere to be found.
However, when certain mods are applied to a Minecraft server, Herobrine appears. He looks just like Steve (mentioned above), except that his iris’ are white.
To color him accurately, use the same color palette for Steve, but keep his eyes white.