There's a door at the south end of the station. Go inside and wait for them to call your train number. You'll see people in-the-know lining up outside.
You wait in the station until they announce the train is boarding, then you go to the track they direct you to or you can line up in the boarding area ( it's to the left when you walk out of the station on the side that the tracks are).
We are flying into San Diego, then taking a train home to irvine. Are the trains always leaving in time.
All of the trains stop in the same spot here and you line up just in front of the lobby doors. A staff member will then guide you to the appropriate train.
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