You can register on the Expo ID registration page. Please note that you must agree to the Terms of Use before registering.

Expo ID login page:
https://usrmng.accounts.expo2025.or.jp/idmng/users/screen/menuScreen　

Detailed instructions on how to set up your Expo ID can be found in the Expo ID Registration Manual, which can be found at the following link.

ExpoID registration manual:
https://www.expo2025.or.jp/wp/wp-content/themes/expo2025orjp_2022/assets/pdf/tickets-index/id_registration_manual_en.pdf