As few heat cycles as possible. First a minute, then three. Keep the rpms up to 1500 steady. No throttle blipping. Normal motor, no leaks or strange sounds, you're ready for the dyno. If done on the street be sure the tune is close and the motor is warmed up before getting on it.
Hastings, HD ring source, suggests this. Roll-ons not high rpm stuff. Load and unload the rings and they seat quick.
https://www.hastingsmfg.com/ServiceTips/breakin_procedure.htmJust the way I do things not essential YMMV, the hone pattern and RA will determine more so ask the machinist that bores your parts for recommendations.
I use a break-in oil like Joe Gibbs or Maxima Maxum. Straight 30 is fine. This is NOT for the ZDDP, that is a car lifter deal, but for the lack of friction modifying polymers. Pull it out and change filter after 50 miles of load and unloading the rings. Motor is broken in now or it will never be broken in. I also use Total Seal dry lube on the cylinders and their assembly lube very sparingly on the skirts and entrance to the bore, and a drop only in each ring groove.