To make a BMW emblem you will need the fallowing materials:

Patience
A sheet of metal aluminum works or steel anything that conducts electricity.
illustrator
Water jet
Powder coating gun
Powder coating powder
Laser cutter
Painters tape
Calibrator to measure with
ruller
pencil

Step 1: Step One

Go online and find a BMW logo High res.
bring the file into Illustrator and out line the logo (circle) to the dimension you desire.

Now if your emblem has screw holes draw those in by using a caliber to measure to make sure the hole match up later when you instal your emblem.

Once you have drawn out you file save it as the oldest illustrator version and open it in Flow path. MAke sure you put some tabs to hold your emblems in place.

If you don't know how to use the water jet visit you local Tech Shop and take a class.

Step 2: Step Two: Cut and POwder Coat

Now that you have visited your local Tech Shop and taken a water jet class and use the file to cut out you emblem from you piece of metal. you are ready for step two

Take you metal piece and powder coat it on both side in case you make a mistake you have two chance to laser etch it correctly.

good Job.

Step 3: Step Three Laser Time

How that you have you metal piece cut and powered coated you are ready to prep you material for the laser.

Using a pencil and ruler draw out a square that the circle you cut out fits perfectly.
Measure it and it draw the same size square in illustrator.
Draw out your piece of metal in illustrator and the square you dimension out in reference to all four side of you metal piece.
Now paste in the high res logo you made in step 1.
check you laser for etching settings
Laser way once you have place the laser pointer on the top left corner of the square you drew out on the metal.