Alacrity…

… is a splendid virtue.

Remember how much better everything feels when you…

… step lively / jump to it / look alive / haul away / do it now.

Remember the quickness, lightness and sureness of step, and how much you can get done.

Alacrity makes even arduous tasks seem better because with it, they’re quickly behind you.

See also: 

Eagerness. Willingness. Readiness… Treasure Island 

I'd love to hear your thoughts and recommended resources...