Whatever anybody tells you. SkyWest and they're whole HR crew there really want to hire you. Very professional organization and straight forward throughout whole interview process. Unfortunately I did not make the cut at the end of the day due to a glitch on my paperwork.

The day is wicked long but doable as long as you stay relaxed. I know that sounds crazy but you have to maintain and just be relaxed as much as possible. Just remember these guy's were just like you at one point and the job is yours to lose.
The interview started right about 0745 after getting there around 0715 from the hotel. Make sure you take the 0700 or 0715 vans from whatever hotel your coming from. Most stay at the Candlewood but I stayed right across the street. And was there at about 0715 and waited in the Holding room with the other five applicants. Total of six of us and I believe only one made it through the whole process possibly two. I really hope these two guy's made it and they're in ground school already.
Out of the six of us, three busted the sim and I was washed out due to paperwork not being in order that they did not bring to my attention until right before my CRM excercise. Out of the six applicants two were Part 121 guys, three cfi's including myself and one 135 guy.

Sim ride I had was the full ILS 8 into Burbank. Took off, climed to 8k after some traffic alert vectors. He gave me vectors to intercept some radial off the lax vor. I think it was like the 356 radial off of Lax that was a feeder direct the OM for the appch. I should have did a par entry but did a td but explained my way out of that. Shot the full ILS and started the missed again. When he had me do the missed I think he was looking to make sure I climbed within the gradiant that you had to climb out at. Make sure you do and call out all your checklists ex. Before T/O, T/O, after T/O, Enroute, Approach and before ldg checklists. Also make sure you brief the approach before the sim starts and hammer the missed approach to him a couple of times while flying. My ILS and A/S on the approach was pegged and that is what they're really looking for. Good scan and procedures.
The tests are easy if you study the ATP gleim, I think I aced that. The mech aptitude is a little tricky but just read the questions through and you will be fine. If you have the ASVAB booklet or OCS test booklet just read the Mech Apt questions on gears, ropes, pulleys, hyd's and you will be fine.

The HR/TEch interview lasted all of about 75 min with a break for lunch in the middle. Hr interview was very straight forward and they are just looking to see why they should hire you. The tech interview he hammered me on the Piper Seminole's Governor system and electrics pretty good. Went pretty deep into WX but I nailed that so he moved onto Jepps enroute and Approach plates. Real simple stuff like MEA's Moca's, Class D and where to find the hours of operation. He broke out an approach plate for RNO ILS 17l I believe and had me figure out a VDP for that. Know the formulas for VDP DME and Timing method. Overall the Tech interview was more of a learning experience than anything else. I would say I knew 90-95% of the questions he threw at me. The other 5-10% were questions like how do you determine your vis if it's reporting below mins at the DH or MDA. Than you get to your DH/MDA and the vis is above mins. Basically have your ducks in a row in case you get asked by the feds on the ramp after landing in reported low mins.
Overall a very long day with the outcome I did not expect. Be yourself and you will be fine. Expect to be there until at least 4pm if not later and just do the best you can. Control the things that are within your control and do the best you can with the things that are out of your control. They invited me to re-apply within six months which I was psyched about but did leave really bummed out.
They are probably the best regional out there to work for and sell yourself as much as you can. Lots of growth potential and that family environment everybody wants to work for. Good luck and try to relax!!!

Everything that has been said before. These are the biggest points - 1. In my opinion the Military flight aptitude tests are better than the ASVAB for preparing you for the Mechanical Comprehension. That book has more problems and they were almost identical to what I had in the interview. 2. There is absolutely no substitute for prepping for the ATP written then any ATP test prep book. I used ASA and not the Gleim book. Don't think it makes a difference. 3. Is sim prep absolutely required? No, however, I strongly recommend it for no other reason then to feel more comfortable during the interview. Had no problems with American Aviation. 4. EVERYBODY needs to know Jepps. I am military but I got grilled for over an hour on Jepps charts and approach plates. They might be more understanding when they sit down to talk about it afterwards but during the tech portion of the face to face, my interviewer did not give an inch on the Jepps. 5. HR was pretty standard - tell a good aviation story, have a point and speak to how it contributed to your growth and that of your organization. 6. CRM exercise was low threat but be a good team player, gather as much information as you can from EVERYONE, weigh and verbalize all options and make a decision in less then 7 minutes. Good Luck.