Check to be sure it has proper oil level and a filter on it. Next, take the spark plugs out, and install a good oil pressure gauge. Crank it over with the starter until oil pressure goes up on the gauge. Reinstall spark plugs. and start the engine, noting oil pressure. If it goes up and holds steady over 10-15 PSI at idle, that's good. If higher, that's better. If it seems too high, you should look for problems.
There are many different ways to star the break in procedure. Personally, I would run the engine at 1500-2000 RPM for 10 minutes, pull it up to 2500 for a few minutes, and drop back to idle-1500 for a few more minutes. Check oil pressure. If its still holding over 10PSI at idle, things are going well.
Some guys will change oil at this point, some won't. I don't. Take the car for a 10 minute drive, some moderate acceleration, lower speeds, no real loads. If all still seems good, go out for a 20 minutes drive. Cruise at 45mph for several minutes. Using moderate acceleration to hit 55-60MPH, cruise here for several minutes. Allow the car to drop back down to 45MPH, and do this again several times. Find a road where you can coast and accelerate. Start out coasting, and accelerate briskly to legal limit. Do this several times. The idea is to raise and lower temps, as well as create cylinder pressure that will seat the rings.
Take the car home, change the oil and drive as you see fit.
