When I rebuild a small engine, I will let it idle for a few min to warm up. Then just bump the speed up to about half thottle for a few min. Then just run it normal without reaching full RPM's for about an hour or so. Then I would drain the oil. Then run it normal for 15-20 hours or so. Then drain it and fill it with some good Amsoil Synthetic or a good equivalent. That has worked well for me on many Kohler and Briggs rebuilds! But you should see if your owners manual has any info.
Just do a few heat cycles, warm it up(usually only anminute or two) then blow it out for a sec, let it idle down and then kill it. Wait for it to completely cool and repeat twice. Change the oil and you should be good!