Here is a quick guide. You need basic+ linux skills. You will get from 0.2 to 1.5 khash/sec completely free.
1. Join Amazon EC2. They offer free tier for new users for 12 months:
As part of AWS’s Free Usage Tier, new AWS customers can get started with Amazon EC2 for free. Upon sign-up, new AWS customers receive the following EC2 services each month for one year:
750 hours of EC2 running Linux/Unix Micro instance usage
750 hours of Elastic Load Balancing plus 15 GB data processing
10 GB of Amazon Elastic Block Storage (EBS) plus 1 million IOs and 1 GB snapshot storage
15 GB of bandwidth out aggregated across all AWS services
1 GB of Regional Data Transfer
So as a new user you will get 750 hours of EC2 running Linux/Unix Micro instance usage.
And what is a micro linux instance?
Micro Instance 613 MB of memory, up to 2 ECUs (for short periodic bursts), EBS storage only, 32-bit or 64-bit platform
Not much, it will mine with 0.2 to 1.5 khash/sec. But you'll get it for free.
2. Launch a new micro linux instance, donwload and run cpuminer. Mine for free. This might be useful for step 2:
sudo yum -y groupinstall "Development Tools"
sudo yum -y install git libcurl-devel python-devel screen rsync
git clone https://github.com/ArtForz/cpuminer.git
cd cpuminer
./autogen.sh
./configure
make -j
nohup ./minerd --algo scrypt -s 6 --threads 2 --url http://yourpool --userpass user:pass
Enjoy.
If you like it consider a small donation:
LTC: LLARLyxXXQKdCwcL36MigpkezRBbpJ2LVA
BTC: 19bryXyWwczic43JEcT2dwjTAe12ABX45U