In addition to the many good replies you already received,how about finding other things that you really enjoy doing in your "real life"? Do you want to do sports? Act? Volunteer? Walk dogs? Earn some money? Do something nice for someone else? Go to the movies? Up to you, but time spent on the phone is keeping you from enjoying and experiencing lots of other things ! Including real face to face time with real people. Its your choice. 

Remove the battery for six or eight hour periods. Only power it for one hour at a time.

By not being on the phone so much. You're looking for some kind of secret method?? There isn't one. You just stop. You use your willpower, assuming of course that you have any.

You are not a puppet.   Turn your phone off.

Maybe put it in an envelope with a time written on.  DO NOT USE it if is not time....except in emergencies 

You don't really want to do it or else you would because you aren't doing anything that may save your life.

Don't charge it that often let it die or set a time limit on your phone.

Self-discipline. 

No one is forcing you to look at it.

Self-control is a very important life skill.

Go for a walk. Use your mind to talk to yourself not the phone

Put it in a drawer and do without it for a while.