project sketch to another plane
THERE IS TWO KIND OF PROJECTIONS
More complicated than Shashank Agarwal but sometimes it's necessary. If you convert entities from a sketch to a new plane, the new sketch is a projection perpendicular to its plane. There is a method to project the sketch perpendicularly to itself: Using: "Insert-Curve-Separation Line" on a surface, not a plane. After separating this surface, you get borders. You can make a new sketch on the surface plane and convert the contour entities. The separation projection is perpendicular to the initial sketch.