Here for your pleasure is my recent experience:
Coming in, it's a LONG walk from your gate to immigration without a lot of restroom opportunities. If you need one, do it sooner rather than later. Once there, employees are very busily and loudly directing people with various passports into various lines. Pay attention. You will eventually get to an ATM-like terminal where you insert your passport and they look upon your face; there's a sign saying essentially we now check everyone coming into the country. The gate will open and you're in. Once you get your bags, read the overhead signs and it's easy to figure out how to get a train or taxi.
If you're on a codeshare, which it seems most flights are these days, be prepared to be tossed back and forth between the two airlines until the dust settles. I was on a Virgin flight through a Delta reservation. When leaving LAX, since we had Delta boarding passes we went to the Delta terminal and the agent apologetically said, yeah I know what the pass says but you need to go over to Virgin and get a new pass from them. Hot tip - if you have Precheck (and you really need to), make sure that wording is printed on your pass. It was on my Delta pass but not my Virgin pass, I realized after a while that arguing with the TSA agent would get me nowhere except perhaps jail so I had to go through the regular line.
When it was time to do online check in for my return flight, the Delta site let me get almost all the way to the end and then would just stop and say this isn't working. On one of the tries I somehow got kicked me over to the Virgin website and they let me complete the process. Come to think of it, this happened last year at CDG between Delta and Air France. When we got to the airport luckily Virgin and Delta are right next to each other, we used the Virgin machine and got passes and then tried to enter the Delta premium econ line. No go they said, you need to visit Virgin. We finally got onto the flight. We also saw the Delta blazer employee nearly get into it with the Virgin blazer employee, I think this family needs a little counseling.