After submitting your application at any major hub you're likely to be contacted by a lead HR rep. You'll be called in for a group interview/tour where every potential employee is briefed on the physical requirements and such things. Basically, if you can show the HR rep that you know what is expected of you and you will work hard they will call about another interview within a few days. If they do not call again you may go in person to the HR department and ask about whether or not they will give you a shot, this will seal the deal. If you go in person and show you have high interest they will set an appointment for you on the spot and then you have the job. The interview questions are as simple as this, "Can you lift 'n' amount of pounds nonstop?", "Can you show up on time every day?".