German grammar is one of the most difficult, start to learn it at university is a good idea because you have the maturity that's required in order to start your learning on good bases. I started learning German at university 2 years ago as well and now I'm well able to have a conversation with some German friends in German.
What I advise you to do and what I did is to learn as much vocabulary as you can and to do learn BY HEART the grammar rules and the cases (Nomitativ, Akkusativ, Dativ and Genitiv).
I used an app called VocApp a lot as well because you can create your own flashcards and gather them in courses, which is great to learn to vocabulary you've seen in class for example.
You can try vocapp. They have recordings of Russian pronunciation which you can practice along with learning new words. Here's a sample set so you can see how it works: http://vocapp.com/25-must-know-russian-verbs-flashcards-196278