Math is a language. The only way to get better at "speaking" it is to practice it as much as you can. The more practice, the more fluent you'll get with it. Try to connect it to things you already know. Then build from there. If you are a visual learner for instance, then try to make a graph to see what's going on with the function. Speaking of which, there are free graphing tools such as Desmos and GeoGebra that I use all the time when I'm helping students. Those tools also help me visualize how to solve and quickly confirm answers. Not to mention they are packed with tons of other features.
Also, part of getting better with math is asking questions. Don't be afraid to do so. I'm sure the teaching assistant would be more than happy to help. Talk with your classmates as well about the questions so that you better can grasp the material. Sometimes all it takes is a re-interpretation of the question so that things click better. I've found that if student A helps student B, then student A tends to understand things better. Of course it's not a hard fast rule by any means. It's purely anecdotal.
Another avenue you could take is to watch lectures and videos online. Then scroll down to the comment section (if there is one) to see what everyone is talking about. If there are questions being asked, try to see if you can answer them. You don't personally need to post a reply to them, but try to see if you can put yourself in the role as a teacher. This could be a way to practice.
Then lastly there are various free online articles and e-books to help your further studies. The downside may be that it's not interactive and may be full of complicated notation. But after getting a better grasp with things the notation isn't too bad.