What is it? How do I do it?

Cryptocurrencies are decentralized currencies. The US Dollar is centralized since there is a single source of truth who has a theoretical balance sheet -- the central bank in the US. With most cryptocurrencies, a public ledger is used to ensure there is no single source of truth.
Crypto mining is the process of generating cryptocurrency using acceletarted hardware like a GPU or CPU. The single miner performs math problems, and when a solution is reached, the miner raises it to a mining pool, and a profit is shared among all miners in the pool. People generally join mining pools as it provides more consistent gains.

2. Sounds great! How can I start?

Most people do not have the hardware required to mine cryptocurrency efficiently. Additionally, Crypto mining on the AWS/Azure cloud is flatly unprofitable. Crypto mining of Ethereum and Bitcoin is also generally a no-go, because the costs will outweigh the mined cryptocurrency.

3. Mining Garlicoin on the cloud

Here is the reference I will follow below. Please go to garlicoin.io to learn more about Garlicoin.

I chose Garlicoin because I liked the name and it was relatively unknown.

a. Create a Garlicoin wallet. I recommend garlicoin-core

b. Pick your Ubuntu/Linux instance type. In my case, I am using an AWS EC2 G4DN.XLARGE, which I found to be most cost effective of the few GPU Optimized instances I attempted.

c. Run this startup script on my GitHub, which installs relevant packages using apt-get.
This can be made into a launch script to configure the instance on startup.

d. Run the command: ./ccminer --algo=allium -o stratum+tcp://freshgarlicblocks.net:3032 -u MGHDr9KLMDrZN5Dykbgdr1KpaeSv8tXMBS --max-temp=85 --submit-stale

4. Conclusion & Recommendation

I do not recommend mining cryptocurrencies unless a) you have free electricity or free cloud credits. If so, target a small cryptocurrency that you predict will blow up in value, thereby making the costs valid.