LOL, the "break in" the OP is referring to is the exhaust smell break in...ie, the cotton/packing used in the muffler burning, which is normal as you drive and break it in...there's no procedure OP, drive it like you stole it. Literally. And tape it, so we can enjoy the tone..
2012 335i Mineral Gray
M Performance Whore: PPK|Exhaust|Brakes|Performance Suspension Struts & Springs|LSD|Black Kidney Grilles|CF Spoiler and Mirror Caps|Bav Stage 1|400Ms|ER CP/IC/DP | Dinan CAI |BMWF30.com