Not One's Cup of Tea
DEFINITION: Something that a person finds undesirable or uninteresting.

EXAMPLE: Although I'd attend the gallery showing if you have no one else to go with, that kind of thing just isn't my cup of tea.
"Gosh, I can't thank you enough for your help! I looked over your edits/suggestions, and I think they make the essay much better. "
C. Nelson
Graduate Student
University of Colorado