My advice is everyone else's advice: 1. Read Cracking the Coding Interview and books like that. 2. Brush up on HackerRank, CodingWars, LeetCode, and sites like that. 3. Don't forget to work on design problems. 4. Practice in front of friends. The questions were hard, but the environment was low-pressure, so don't feel like you have to super-over-prepare, either. I don't remember the exact questions because it's been a while, but the coding one was about searching for a particular node in a tree or traversing a tree or something, and I had to state the runtime at the end. The design question was to sketch out the architecture for an app for a small business. You needed a way to manage reservations/rentals, store and update customer accounts, bill the correct amounts, and send various email notifications.
