How to listen to music on youtube without the app being open for the iPhone?

I used to be able to listen to music on YouTube without the app being open but now it won't let me because I updated the software.

There's no possible way, I wish the old youtube app was still available!

Put on a song on YouTube and hit the 'Sleep' button. Double tap the home button twice, where you're still on your lock screen, and press the play button. If your update is different, find a way to play your music while still on the lock screen, and then unlock your iPhone. Hit the home button once and then hit the sleep button again, and then press play from the lock screen. Unlock your iPod and there you go!