do it fast!

早速(さっそく)	Immediately. $$$

速やか(すみやか)	Like 早速, but emphasizes doing something FAST or promptly, rather than STARTING immediately. Usually used in ONLY an office – give this document or procedure top priority.!

急いで(いそいで)	Do it fast! Pretty much the same as 速やか, but you can use it in any situation.