How to add artwork to music on iPhone?

What I've tried doing is going into iTunes, then right click on the song and click on get info, then add artwork like that. But it still doesn't show up on my iPhone. Am I doing something wrong?

The image is probably broken.

I have like ocd wen it comes to me having artwork on my songs lol.
ok so i normally go to google images rite in the song and artist you want, save the pic you want onto your laptop.
then open itunes, rite click on the song you want to add your art work to, go to more info, then click on artwork, press add, find the pic you jus saved, press open, the pic will then go into the box press ok.
there you have it you should have your artwork.