There are several Getting Started videos on main page which you can see here:

If your Digital Audio Player shows up as a disk drive when you plug it into your Mac, watch this:

If you have an Android Based DAP that does not show up as a disk drive, but needs Android File transfer, then you need to remove Android File Transfer, and watch this video:

If you want to be able to have a faster sync for Android and sync using the USB Cable AND by ejecting your SDCards from your DAP and connecting them to your Mac using a reader, then check out this video: