Double click the download file to install the mining software and follow the prompts. The software will run a benchmark to determine how much it estimates you can earn per day/month.
Bitcoin mining uses the computing power of your machine to mine, which can run up your electricity bill. Imagine if you could install your miner on other computers, and harness someone elses machine and electricity? Brainstorm all of the places near you that may have idle computers that stay on 24/7 that you have access to. Here are some examples:
At your work office. How many PC's are in your office? Install the miner on as many as you can.
Retail stores. The display PC's in retail stores are usually pretty modern and powerful, and run 24/7. Turn each into your personal Bitcoin miner.