I've heard that "breaking in" today's engine's isn't really necessary.
But, I still follow the advice my Dad alway's gave me.
For the first 500 mile's, I avoid "hard" acceleration's, I avoid driving at a sustained speed for too many mile's, I avoid the higher RPM's, and I also change the oil after the first 500 mile's.
Maybe it's "old school", and a little "over protective", but it's alway's worked for me.