1. something is the result of somebody's own actions
this mess is entirely your own doing
Generally, when you say that 'something is somebody's own doing,' you are saying that it is their fault; that their mistakes or poor decisions have led to that outcome. For that reason, it is often utilized as an accusation or as an admission of blame, and is similar to the phrase 'you have no one to blame but yourself.' However, this expression can also be a means of crediting yourself or somebody else with something, sharing a similarity with 'thanks to me.'