You first apply online like normal. Then you answer some simple math questions and then record yourself answering some simple behavioral questions. After about 3 weeks they'll let you know if you made it to the first round. Then after 2 weeks they'll let you know about if you made it to the second round. I didn't make it to the second round but I heard that the 3rd round has to deal with a team project you have to present to a group of people that work there.