First off, welcome to E90post.
You have installed new plugs or not yet? How many miles on the car? Got a name?
You can also search for "misfire" and read through the typical fixes. 1) install new plugs. 2) move coils, see whether the misfire moves with the coil. 3) possible injector(s), excessive carbon buildup, bad PCV allowing a lot of extra oil into the intake, bad O2 sensors, etc.
E92 335i/6MT Dinan Stage 3: intercooler, oil cooler, intake, flash, exhaust, LW dual-mass flywheel.
Vishnu PWM methanol custom trunk mount, Diffsonline 3-clutch Salisbury custom diff, Ohlins Road and Track coilovers, Vorshlag camber plates, much more...
E28 M5 w/ buncha stuff, R171 SLK350