To "prepare a piece" from a downloaded file like , you simply need to extract the contents so you can use the game or software inside. How to Unzip on a Mac
: Open that folder and look for an executable file (often ending in .app or with a specific icon) to start the program. Troubleshooting Futaken_v0.029R_Mac.zip
If you are trying to "prepare a piece" in the sense of a involving zippers (as suggested by some general search results), you would typically begin by printing and cutting your pattern pieces and marking your notches. Are you having trouble opening the file , or To "prepare a piece" from a downloaded file