If you dont want to use sudo before the command then edit the 4th column in /etc/fstab to include “user”. After that any user can mount the USB stick.
Example
usbfs /proc/bus/usb usbfs noauto,user 0 0
Or if you want only a particular user to have mount and un-mount permissions then edit /etc/fstab to look like
usbfs /proc/bus/usb usbfs noauto.uid=<UID_USER> 0 0
where UID_USER is the UID of the particular user.