If you're like me, this phenomena will occur at least once per writing assignment. You could sit and stare at the screen, hoping for the right words to come, or you can tackle writers block head on. I recommend the latter. Though some of the advice may seem counter-intuitive, these tricks have always worked for me:
Take a Break
We're all looking for excuses to watch just one more episode of our favorite television shows; when you're stumped with what to write next, go ahead and watch one. It's important to give your brain a break every once and a while. Leave the computer, re-calibrate, and return to your paper when you've gotten enough distance from it. Although it may seem counter-intuitive, taking a break can do wonders in regards to writer's block.
Go for a Walk
If restraint isn't one of your better qualities and you find watching just one episode an impossible task, do what I do: go for a walk. Unlike watching T.V., walking can subconsciously generate new ideas. If I'm stuck on a paper and go for a walk, I can usually find a way to push past writer's block by the time I get back.
Write it Out
One of the most common causes of writer's block is the desire for everything to come out perfectly the first time. If you halt at the end of each sentence to re-read and then edit what's just been written, this trick is made for you. Instead of focusing on saying everything perfectly, just write what comes to your mind first. It might look like gibberish, but it works the same way brainstorming does. Just remember to edit your work when finished!
Change the Scene
Have you ever wondered why so many fast food restaurants brand themselves with the colors red or yellow? They do this because it triggers the parts of your brain associated with hunger and happiness on a subconscious level. In this same way, the room you most often work in becomes associated with stress, and that can get in the way of productivity. Try taking your work somewhere new, perhaps a local coffee shop, and see if that does anything for you. If not, at least you got a cup of coffee.