reach for the sky

Set very high goals, aspire to the best, as in I'm sure they'll make you a partner, so reach for the sky. The sky here stands for high aspirations. Also see sky's the limit.

Put your hands up high, as in One robber held the teller at gunpoint, shouting “Reach for the sky!” This usage is always put as an imperative. [Slang; mid-1900s]