How do I get all the music from my MAC on to my iphone6?

Import it into an iTunes library and then sync the iPhone with that library.

(114221)

Connect the iPhone to your Mac, open iTunes, click your phone's icon in iTunes, go to the Music tab, choose to sync all music, then click Sync.

Matt

How to Sync to the computer.

http://support.apple.com/kb/HT1351

Note make sure you are signed in with the same Apple ID on the Device and Computer

• Install the latest version of iTunes on your computer if it isn't there already
• Connect your phone to your computer
• Click on its name in iTunes
• Uncheck "Manually manage music and videos" if it is checked
• Click "Apply" if prompted to do so
• Click on the word "Music" near the top center of the screen
• Check "Sync music" if it isn't already checked
• Click "Entire Music Library"
• Click "Sync" in the lower right corner of the screen.