The following links will take you directly to the installation page in Salesforce:
Important! Make sure to always install “For Admins Only”.
Install Booker25 v4.81 in a Sandbox
Install Booker25 v4.81 in Production
For a detailed overview of Booker25 releases, check https://www.booker25.com/release-notes/
If you are installing this in a new environment, please make sure to follow the following steps: https://gen25-jira.atlassian.net/wiki/spaces/BPD/pages/426037