Auto body repair & detailing: Touch Up Paint on 2008 328i BMW, vehicle id number, factory paint

Question
i recently backed into another car very slowly and it took a line about 1 cm thick and 5 inches long off of paint. i would like to touch this up myself. This will be my first time and i was either hoping you can give me advice or online manuals to read and/or the steps to do each procedure. Can you help?  

Answer
J.... NO PROBLEM.

OPTION #1. CALL THE DEALER AND GIVE THEM YOUR VEHICLE ID NUMBER LOCATED ON THE DOOR JAMB OF THE DRIVERS SIDE DOOR.THIS NUMBER WILL DECODE THE BMW PAINT CODE THAT IS ASSOCIATED WITH YOUR CAR.
PURCHASE A TOUCH UP BOTTLE.

USING THE SUPPLIED APPLICATOR BRUSH A LIGHT COAT ON ...WAIT 15 MINUTES AND BRUSH ANOTHER ONE ON.
REPEAT UNTIL PAINT IS EVEN WITH THE FACTORY PAINT. THE OBJECT IS TO FILL THE SCRATCH WITHOUT OVERFILLING THE DAMAGED AREA.

KEEP IN MIND THAT THE FINAL APPEARANCE WILL LOOK A SHADE DARKER THAN THE SURROUNDING AREA.

GOOD LUCK
MIKE