i agree with being "teamy" with your sim partner, if you've got a captain upgrade in the left seat learn as much as you can from him, if you've got another new hire, then you guys should be learning as a team. If both of you come from a CFI background that should help, as you'll know how to give each other pointers, or other advise, and hopefully you'll both know how to take advise as well. You're instructor is there to teach you how to fly "THE" plane, but not how to fly "A" plane, so be brushed up on your instrument procedures, i'd use microsoft flight sim, i bought the ERJ PIC program for mine, worked nice for getting a scan. But don't be expecting to land the sim because you can land your flight simulator, as they're two different things, same with the sim and the airplane. If you are going to use MSFS, all weather is at minimums, all approaches are to minimums, or to a missed, etc.

But everyone else is definitely right about knowing your flows/profiles before you hit that sim box, and have a good idea of how to use the automation to fly the airplane.