There is no way to earn money from BTC mining, so it's better to try out some of the altcoins. After the SHA-256 algo (e.g. BTC) the second most popular is I think the SCRYPT algo (like Litecoin, Feathercoin...) where the difficulty may be much lower. Before you want to buy some mining rig from ebay, you may want to test the method how one can mine altcoins. Hashing can be done by CPU or GPU. GPU hashing is much more efficient, but not every notepook/PC have a good ati/nvidia GPU so now just try it with CPU, that's the easiest method. Hashing will use your CPU on maximum power, and it will generate a lot of heat, so it is NOT advised to run the mining software for a long time on a notebook (or a PC with a shitty cooler)!!!

First make a litecoin address, and sign up at a mining pool.

Now I based the tutorial on mining Litecoin on ghash.io's pool because if you sign up to ghash you instantly get altcoin addresses. Ghash is run by CEX.IO, you can register here, and than start. You can trade with coins on cex.io, ghash.io is just for mining.

1. for usage on ubuntu

Open the terminal, press Ctrl+Alt+T
Make sure your OS is up to date, type in:

sudo apt-get update
sudo apt-get upgrade -y

then type the following:

sudo apt-get install libcurl4-openssl-dev libncurses5-dev pkg-config automake yasm

git clone https://github.com/pooler/cpuminer.git

cd cpuminer
./autogen.sh
./configure CFLAGS="-O3"
make

then start the miner with the specifics of your mining pool, for example:

./minerd --url=stratum+tcp://ltc.ghash.io:3333 --user=faucet.4 --pass=x -t 4

url is your preferred pool’s address, user is your username and a worker, pass is your password and it could be random (this is for ghash.io especially)

2. usage on windows (64-bit)

download pooler's cpuminer from here: https://sourceforge.net/projects/cpuminer/files/pooler-cpuminer-2.4.4-win64.zip/download

unzip the folder

make a plain .txt file in that folder

open txt file, type this: minerd.exe --url=stratum+tcp://ltc.ghash.io:3333 --user=faucet.4 --pass=x -t 4

(of course you have to replace user/pass with your own from ghash.io or other pool you may use)

save this file as .bat file, for example startmining.bat

doubleclick on the .bat file

and now you are mining litecoin yay!!!

pooler's cpuminer has a lot of command for fine-tuning, you have to make it for yourself compared to what are your system's specs, the -t command is for the number of cores in you cpu. Mine is a core i3 with 2 cores and hyperthreading (virtually +2 cores) so i use -t 4
it is advised to check the core temps with a software

Have fun! Feel free to ask me.

source: http://minersguideblog.wordpress.com (english) and http://egesznapagepelott.blogspot.com (hungarian)
*if you found it useful, you may donate: 1KnLMJSdeCayVVEy4jav426SckGyaTr2zP :D:D