I'm a student as well and i don't recommend you to invest into cloud mining instead just hold your bitcoin and wait for it's price to increase because you're gonna need to wait a long time before you're able to get a profit from it. (But i guess i'm a little bit late to tell you that.) Also i don't recommend you to trade bitcoin unless you have enough knowledge about trading because trading it's not easy, many people said that they earn profit through trading but it's not as easy as 123 but there's many things you need to consider first in order to start trading such as (Capital, Strategy, Different Plans and Good Decision

There's a lot of things you can do in order to earn bitcoin without investing money you can start here in the forum by joining different jobs such as:
- Signature Campaign
- Social Media Campaign
- Bounties
- Translations
- And you can offer services here in the forum such as designing, managing campaigns, escrow etc.

All of the things i stated is just an opinion it's up to you if you're going to follow it or not.