1.applying online (you can apply for all departments, since they have different process,but one of them will be stoped until the result of the first one be clear.
2. Interview with 2 or one design managers. They ask about your experience, challenges, communication, design process.
3 craft interview, You should prepare one or 2 projects and represent for the interviewers. Be date driven and user centered.
4. Interview with a developer and a product manager, all about problem solving, achievements, tram work, fixing conflicts.
VERY Important note:
Let me share an interesting experience in this case. 4 month ago I applied for 3 department. One of the team feedback about the craft interview was super amazing, they realised how I solved the problem and the complexity of case was clear for them. But I was rejected in fit interview. Another time I applied for another department and rejected for the craft interview! Can you believe that? And the hiring manager pointed out the project didn't have complicity and good enough for a Senior level.
I can not believe that there is no any standard in a huge company such as Booking !
What happened to the third one? Position filled! Two times!