To upload presets onto the One, first insert a properly formatted flash drive into the USB port. Make sure the presets are in the main part of the drive and not inside of a folder.
Once you have done that, click "Settings" and then press the soft button above "Library" on the screen (it will be the second from the left soft button above the screen).
Once in this menu scroll to "Import", press the large encoder, highlight "Presets", and press the large encoder again.
If the drive is formatted and the presets are in the main part of the USB drive you should see them listed in this menu; from here you can choose individual presets to load or click "Enable All" (this will be the third from the left soft button above the screen).
Once you have chosen the presets you would like to load you can hit the soft button above "Import All" on the screen (it should be the soft button on the far right on top of the screen).