There's two methods of getting this achievement.
Method 1:
Dashing into a pool of water five times. Dashing into the water, resetting and quickly dashing back in again.
Method 2:
Equipping the
Rosethorn Ring and
Green Ribbon Badge to give you 2 additional dashes. The Rosethorn Ring can be found within a chest in the
Jungle biome (Tanglegrove) and the Green Ribbon can be purchased at anytime from the
Badge Vendor. Once both equip simply dash five times in a row.