A self-contained finger sleeve, having a cover, a thumb pocket and a four-finger pocket, each having an opening: one edge of the opening of the four-finger pocket is connected to an edge of the opening of the cover: an opposite edge of the opening of the four-finger pocket is connected to an edge of the opening of the thumb pocket via a U-shaped connecting strap: in a self-contained condition, the openings of the cover and the four-finger pocket face towards each other to define a storing space that stores the thumb pocket and the U-shaped connecting stap: in an unfolded conditon, the four-finger pocket is flipped inside out and misaligned with the cover; the thumb pocket is exposed from the storing space and positioned on one side of the four-finger pocket flipped inside out the thumb pocket and the four-finger pocket flipped inside out form an ergonomic finger sleeve.