Honor caps will increase with each season, but the maximum bonus for Honor will always be at 35% extra health and 20% extra damage in PvP. Honor will always be available through stat replacement, which requires a special item earned through taking part in PvP matches. In short, you’ll get more Honor stats by taking part in more PvP combat, and PvP combat will allow you to gain Honor stats which in turn make you better at PvP. It’s rather straightforward as progression goes, really.
Source: Official Site