I applied online via a link from my friend. I was told, despite my Bachelor Degree, I had to take an aptitude test called the Work Keys test. Very easy stuff if you were even an average student through high school. When I passed that, I had a 1 on 1 interview with the recruiter. Pretty standard interview setting. The interviewer asked a lot of "Why this job?" questions repeatedly throughout the interview so be sure to answer the same.
She made me an offer, which is take it or leave it, and I accepted. From there, you have to come back and take a respirator test and a medical physical to get fully cleared to take the job. I unfortunately did not pass the physical because they discovered I had a medical condition that requires surgery, so my offer was rescinded. Be sure you are healthy and in pretty good shape medically because the physical is the most thorough part of the entire process.