Best place to learn Mandarin by yourself

Dear Chinese expats/locals, I have been living in Ningbo, China for two years now and my Chinese is very basic. I can survive but can barely converse with a local I need to get better and much better in the next 8 months. I need to do it by myself for the most of it as I study engineering and have practically no time to do it apart from the two months holiday in the summer

Any recommendations on how it could be done so that I can begin level 2 instead of level 1 in the summer?

Thanks!

EDIT So to summarize what I gathered from these incredible people on reddit:

1. It's hard only in the beginning to learn Chinese. The most important part is dedication and living through the frustration.

2. The tips, books and material recommended by u/hooiYA are godly.

3. Venture out and try to talk to random people. Take courses if you can, otherwise flash cards from yellowbridge.com are helpful

4. Keep practicing. and get a chinese girlfriend maybe.

You peeps are awesome