The Brainliest Answer!
You know that you can find Justin Bieber posters at any store.
Anyways, to add more details and make it look a bit crazy, as fans are a bit crazy, 
1) Take a Justin poster and with a black marker and make an arrow from him that says, I Love You!
2) Make a few hearts around him and make a little cupid.
3) Colour it with bright colours. 
4) Your friend can decorate the rest according to her choice.
2 5 2
Cool. I LOVE JUSTIN!! But i am not such a great fan like my friend.And i need to make the perfect gift for her. Anyways cheers!!
Okay. So friends?
Please open this attachment.i have made a poster on justin bieber.........
see the attachment
e u will like it
Plz give a poster or some suggestions for a poster. But no matter, never give up!