What is pinking or a pinked edge?
A pinked edge is a zigzag or chevron-cut edge which is achieved by using speciality scissors called pinking shears. Pinking serves a mostly decorative and semi-functional purpose. In he dressmaking process, a pinked cut is often used to finish the seam allowance edges of low-fraying or non fraying fabrics. The jagged edge provides a more professional finish visually, but it is not able to fully contain fabric fraying, especially after the garment's first wash. For that reason, pinking is used with fabrics that do not fray, or with garments designated for single use.
The only way to apply pinking by hand is with a pair of pinking shears. These speciality scissors are very distinguishable given that the blades resemble the imprint they leave on the fabric. The two blades's individual triangle ridges are sharpened moving past each other in the cutting process to leave the triangular imprint behind.
Note: You should never substitute your regular fabric scissors with pinking shears. On that note, pinking shears should never be used to cut your garment pieces, especially when following a paper pattern edge.