If you want to be better at word problems, you need to practice doing word problems.
There's no way around this unless you know of some way to download that skill onto a microchip and implant it in your brain. Of course, even if you do know of a way to do that, you'll need to wait for the download, schedule a time for the operation, two to three weeks of recovery time, and so on. Too much hassle. Better to learn it our way.
As with any other acquired skill in the world, it's all about practice. If you want to become fluent in Spanish, you need to practice speaking Spanish. If you want to become fluent in math, you need to practice doing math. If you want to become fluent in doing a Christopher Walken impression, you need to start practicing your Christopher Walken impression. By the way, you get 0 points for originality with that one. We would've been much more impressed if you impersonated someone slightly more obscure like Nick Offerman.
Who? Exactly.
Math is also a lot like art, which incidentally takes a ton of practice as well. You can watch an artist draw a tree and understand that she's shading to indicate where the shadow is, unless she's drawing one of those shadowless trees, which are so much easier to draw albeit less grounded in reality. In order to draw a good tree yourself, though, you'll probably need to get out a pencil and practice first. Don't be alarmed if your first several attempts look more like spears of broccoli.
Watching someone else, such as your teacher, a tutor, or Shmoop, work out a problem is a good start toward understanding mathematical concepts. Most of us learn best by example, which is our story and we're sticking to it. But we're going off-topic.
While having access to examples is nice, when it comes time for the test, it's whether you can do the problems on your own that counts. Understanding a problem when someone else goes through the steps is different from being able to do the problem yourself. See how we repeated that point and bolded it twice? Hm. Might be an important distinction.
While we're going through examples, have your paper and pencil at the ready—or your pen, if you're feeling cocky. Try to work out the examples on your own. Then, if your answers match ours, you can rest assured that you know your stuff, because we're pretty sure we did these right.
As you do more word problems, you'll notice similarities between some of them. You'll find that many word problems can be grouped into "types'' that are solved in similar ways. Not every word problem will fit obviously into a certain type, and some will fit into more than one type. Unlike with people, you can quickly pinpoint what type of word problem you're dealing with. Stereotyping someone in real life like this is a terrible, terrible idea, but fortunately, it works great with word problems. Besides, some of our best friends are word problems.