LH Side

Remove the battery. < Ref. to REMOVAL , Battery. >
Remove the spark plug cords by pulling the boot. (Do not pull the cord itself.)

Fig 1: Removing Spark Plug Cords By Pulling Boot
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Remove the spark plug with a spark plug socket.

Fig 2: Removing Spark Plug With Spark Plug Socket
Courtesy of SUBARU OF AMERICA, INC.