it's a cinch
It is a very easy task. It's a cinch to get to work at this early hour—hardly anyone is on the road yet.
It's a (dead) cinch.
Fig. It's a very easy task. (Dead means absolutely.) Tom: Did you figure out how to change the tire? Jane: Yep! It was a cinch. Altering clothes patterns is difficult for me, but for Mary, it's a dead cinch.