Start with the same user goals
A visitor should be able to complete the same key tasks in either language. Define those tasks before translating the interface, then review each journey from entry to completion.
Review the details that change direction
Layout, reading order, directional icons, and form alignment need deliberate review. Phone numbers and email addresses may remain left-to-right within an Arabic page, while labels and instructions follow the page language.
Keep context when switching languages
Link a page to its counterpart rather than sending every language switch to the homepage. Give each page a suitable title and description in its language. Test longer text and smaller screens before considering the journey complete.