If you want make some extra money with mining and making a very low (or nothing) investment, read this:

First:

Search a free VPS Server

Second:

Deploy a Server and Install Ubuntu 14.04 or 16.04

Third:

Install the following packages

sudo apt-get install make automake gcc git libcurl4-openssl-dev

Fourth:

Clone cpu-miner with support cryptonight
git clone https://github.com/wolf9466/cpuminer-multi.git

Install Cpuminer
cd cpuminer-multi/
./autogen.sh
./configure
make

Ready !

Now put the miner to work........

./minerd -o stratum+tcp://mine.moneropool.com:3333 -u wallet_address -p x

don't have a monero address ? Open a wallet is very easy
Got to www.mymonero.com...

How much can I win?

Depend obviously of your mining power.
For example, I have around of 35 processors working and i'm making 0.5 XMR each day

The price of XMR is 1.8 - 2 dollars

Do you want to see your mining stats?

Enter here
https://moneropool.com/

Enjoy it!.