The easiest way to manage music and ringtones would be to use the device as mass storage (I have listed the link below on how to enable this mode).
Once the mode is enabled, use the USB cable to plug in your device and computer. The computer should find the device, and you will be able to manage the folders and files on your SD card.
To assign a music file as a ringtone, you can click on the following link below:
***To shuffle the music that you would like to listen to, you can select the “shuffle songs” option in the media folder under the music icon.
I hope this was helpful!