Everyone will tell you something different...

But personally I do this:

Tank 1,2 - Leave the engine at factory settings and start it up. Let it sit there and idle. Once finished, let the engine cool with the piston at BDC (bottom).

Tank 3-10 - Drive the car around going about 1/4 - 1/2 throttle only. You want the engine to run at different rpms.

Tank 11 - start leaning slowly.

The breakin process will last about 1 - 1.5L of fuel.