Arriving at T4 is practically identical to arriving at T3, except that the termional's slightly smaller and less rambling, so the walk to immigration from the plane, on average, is shorter than at T3.

After being processed at immigration and walking through Customs, you go through a doorway. A few yards beyond the doorway, behind a barrier, are the meeters and greeters. Your driver should have a sign up with your name and be in the melee, unless the company's told you different (some co's put their drivers under the 'Meeting Point' sign a few yards away to get out of the crush).

You then have a bit of a walk (100 yds or so to the car itself) to the car park: companies like Just Airports can't have their cars right outside the terminal building.

If you don't see the driver, follow the signs for the Airport Information desk and have a call put out for him.

Much obliged.