Mention that you think some counseling and yoga classes would do wonders for her temper. Take the liberty of signing her up for some classes.
In a casual conversation with her, say, “So are you like still obsessed with that James guy? I mean he is like so ugly. I totally don’t know what you ever saw in him.” Run. Fast.
Write her a theme song; sing/play it whenever she is trying to have an ‘evil moment.’
Make her entire New Born Vampire army wear “James is an Ugly Loser” tee-shirts. Give her one. Do a play-by-play of the death of James until she agrees to wear it. Take pictures! Use them as Blackmail!
Re-enact her death scene with sock puppets. Give her a really high squeaky voice. Repeat this action in front of her army/the Cullens/etc. Feeling evil? Victoria, too, can be on YouTube!
Throw her a huge Birthday party. Invite her army. Have them play ‘pin the tail on the donkey,’ only instead of a donkey; “accidentally” get a picture of James instead of a donkey.
Force her to take Ballroom dancing classes. Pay Jasper to be her partner and to throw random emotions at her the whole time!
Tell her that she would have better luck in life if she was more like Bella.
Tell her that while James was alive he was cheating on her with a one-legged hooker.