Read the owners manual. Basically says that these are broken in from the factory but mostly breaking in the axles. Do not stick it in cruise control for long periods of time on a flat road during the first couple thousand miles and try not to lug it around. Get it into boost pressure once it is warmed up and ensure you let it hangout at idle for about half a song on the radio before shutting her down. These Cummins do not care much about what you do but if you plan to keep it for a long time like myself and others.. what I did and am doing is overkill but is as follows.
First oil change at 5000km's with UOA to see what the factory oil was like and because its always a fun read (filled her up with Amsoil 5w40 ss & Amsoil EAO80 filter). Replaced fuel filters after deleting (4500km's) mainly due to the tank being on the ground while swapping in the Fleece lift-pump (to get out anything that may have fallen in). Ran Hotshot's Secrets Diesel Extreme in the fuel tank at first oil change to dissolve any crap that formed from sitting during trip from factory to dealer. Warm it up before hard pulls but then have some responsible fun with a little weight in the bed. Manual says it will take longer to get the big Cummins to optimal output until she has been ran hard a bit and that is what I intend on doing. Many people think that by lugging her around town staring at the fuel economy readout will provide a long engine life when in reality you will find a responsibly driven and maintained ''worked'' motor to perform best and a plus is your AISIN will thank you for it as it is learning alot about your driving style right now and will perform that way for the forseeable future. Also it is not needed but I recommend some type of fuel additive to boost the crap fuel we get in North America and fill up at a Tier 1 station, you will not believe how bad the fuel quality can be.
One last note to keep in mind is... take a quick look through the forum before creating a thread as you will likely be able to read a ton on the question you have, then add to the end of the already created thread with probably your first question answered but another question that came to mind.. and don't think for a second it would be wrong to revive an old thread or that it will go un-noticed.. plenty of us on here love to beat a dead horse