When you want to use SEISAN with your own data, the necessary directory structure must first be created and your own station coordinates and crustal model must be defined. Both REA and WAV directory structures are created with the program MAKEREA. The program asks for database name (must be 1-5 letters and UPPER CASE), start time (year and month), end time (year and month) and the structure to create (REA or WAV). An output will then show the names of directories created. If a directory already exists, a message will be given. It is possible to create both structures at a time, since the program after finishing asks if the respective other structure should be created.