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If you're thinking about mining Bitcoin with your own hardware, you need to understand exactly how much of an investment you're going to make and how long it will likely be before you turn a profit. Online mining calculators can help you determine if it's really worth it for you to invest in your own rig.  Bitcoin is mined by networks of computers that solve difficult numeric problems to verify Bitcoin blocks of transactions. A block of transactions is made up of a reward subsidy and transaction fees. As of 2020 the block reward subsidy is 12.5 bitcoin, but the amount halves every four years with the amount scheduled to halve to 6.25 bitcoin around the 12th of May 2020. To be competitive as a miner, you will either need an ASIC (Application-Specific Integrated Circuit) unit connected to a computer or several GPUs (Graphics Processing Units) which would be better suited to mining alternative crypto currencies which could be traded for bitcoins. Go to https://www.cryptocompare.com/mining/calculator/ to get an idea of how much you would have to spend in hardware and electricity costs before you turned a profit mining Bitcoin. Keep in mind that for most individual miners, the reality is that they will spend thousands before they mine enough Bitcoin to put them over the top. If you're set on trying to mine Bitcoin despite the cost, you'll need an ASIC miner and a power supply to run it, as well as several GPUs. ASIC miners vary in price depending on their power and efficiency, but you can expect to spend between $1500 and $2000. Once you buy your hardware, you need to be able to set it up. If you don't know your way around circuit boards and computer hardware, this might not be the best hobby for you. A mining pool, such as BitMinter, CK Pool, or Slush Pool, allows you to pool your mining resources with other miners to increase your power and efficiency. Without a mining pool, you would likely mine for years before you managed to get any Bitcoin at all. When you register with a mining pool, you'll receive configuration settings you can use to add your mining rig to the pool as a worker. Your mining rig will start working as soon as you save these settings in your rig. You can control electricity costs by only running your mining rig a few hours a day. However, you're not likely to mine very much Bitcoin this way. Even in a pool, you're only going to get Bitcoin that your rig actually played a part in mining. Because mining rigs generate a lot of heat, keeping it in a basement or garage, where it may be naturally cooler, can be a good option. Not everybody has thousands of dollars to invest in a mining rig, or the tech savvy to keep it up and running –that's where cloud mining comes in. Cloud mining companies own massive server farms of mining rigs and offer contracts that essentially allow you to lease the power of their miner farms for a limited period of time.  There are a lot of cloud-mining scams out there. Go to https://www.cryptocompare.com/mining/#/ to research the company's reputation before you buy a contract. Smaller contracts (typically around $100) may never mine enough Bitcoin to turn a profit. Even larger contracts (several thousand dollars) may take years to mine enough Bitcoin for you to break even.

Summary:
Calculate mining profitability with an online mining calculator. Buy your mining hardware. Join a mining pool. Run your mining rig constantly to maximize profit. Pick a cloud mining contract package if you don't want to build your own rig.