I try to run a newly built engine at various speeds and loads for the first 500 miles. I don't baby the engines but I try to avoid long stretches of steady highway driving during that time. Even on short highway runs I will use some slow down and then full throttle acceleration burst to put vacuum and then pressure on the rings. Hardest part of that is not getting rear ended when slowing or having some joker think you want to race when accelerating.
