The sign for "Monday" is generally done "palm
up." Some ASL books show the sign MONDAY being done with the palm facing down.
I have a
number of associates who consider the palm up/back version to be "more
ASL." I think that perhaps a better way to phrase that
would be to say that "during everyday conversation most skilled native Deaf
ASL signers tend to do the sign for Monday with their palm facing up and/or back."
The palm down version is still ASL, but it is more along the lines of
motherese or "teacherese" -- a "beginner
version" of the sign often taught to 1st semester ASL students. The
palm down version can also be used for emphasis and clarity.
Sample sentence: "Do you like Mondays?" = YOU LIKE MONDAY?
EVERY-MONDAY. (Note: Each of the days of the week can be made
plural by holding the sign a bit higher, then dragging it straight down a foot