To register for GCash, OFWs need to be at least 18 years old and have a valid Philippine mobile number. You'll also need to provide a valid ID for verification, which can be a passport, driver's license, or other government-issued ID. Once registered, you'll need to complete the Know Your Customer (KYC) process to access all features of the app. For more specific details or updates, it's best to check the official GCash website or contact their customer service.