Here’s a nice tip from @goaoio on temporarily changing the dired listing.
'C-u M-x dired' to tweak the options of ls just for this dired. #emacs Sometimes I add 'h' for human readable.
— ε (@goaoio) June 29, 2016
Xah Lee has more information on altering the dired listing, including how to make changes permanent.
If you’re not using GNU ls, you should check your manual page to see what options are available for your system.