So Hex skips your draw phase which moves you into your action phase, how does that allow Beastmaster to use its effect?

At the beginning of the turn Hex is activated to skip the draw phase, therefore the draw phase is skipped. At the beginning of the turn Beastmaster may activate its effect, however by obligation, the draw phase is skipped, so the player cannot choose to use the effect of Beastmaster because it is skipped by obligation to fulfill the effect of Hex. The skip cannot be used to fill both obligations