The days of using cheap mineral oil to bed in rings, cams etc are long gone. There are purpose engineered break in oils that you SHOULD use. I run and recommend Joe Gibbs 'Driven' break in oil and have had good results so far.
Fill it with their break in oil, start it when you're ready, keep the revs up above about 3000rpm for about 5-10mins (try not to let it idle at all) and then go dyno it. Once it's tuned, drop the oil, change the filter and fill it with your chosen synthetic with specs as per your engine builder. I use Joe Gibbs 10W/30.
If you need a hook-up, let me know. Happy to help and see people do the right thing with their new motors.