# For the chief musician

"This is for the director of music to use in worship"

# set to Shoshannim

This may refer to a style or the tune of the music. Sometimes it is translated as "set to the tune of 'Lilies.'"

# A psalm of the sons of Korah

"This is a psalm that the sons of Korah wrote."

# A maschil

This may refer to a style of music. 

# My heart overflows on a good subject

"My emotions are excited about a good subject"

# a good subject

"a noble theme" or "a beautiful word." This refers to the song that he has written.

# composed

to have written or created a song

# my tongue is the pen of a ready writer

"my tongue is like the pen of person who writes well" or "I speak words as skillfully as an experienced writer can write words"