If you’re struggling with a headline, you might want to take a peek at the article “The Art Of Creating Effective Titles And Headlines – Infographic” from Digital Information World. As the title states, it includes an infographic that might just get you unstuck. I think my favorite bit of advice in it is this one: revisit that headline before you publish it.
And my own twist to that advice? Read your introductory paragraph AND check your thesis again before you publish. Sometimes you might just drift away from what your original outline (or intentions) were, and this step might help you tighten up your writing!