You can start mining on your own but this is not profitable or it takes years to give you some profits. Your probability of winning the mining race is very low because you are competing with the whole world miners.
So how can you make mining profitable?
You can join mining pools. A mining pool is a way where miner put together their resources to increase the probability of finding the solution. Every miner awarded a “share” according to the contribution power. That means you get a reward every time the pool finds a solution. The reward is based on how much computational power you shared with the pool.
The largest Bitcoin mining pool is now ANT pool that covers 15 percent of the total coputational power over the network. The second largest mining pool is BTC.com that has 14.3 percent of total power of the network.
The reward per block for Bitcoin is 12.5 BTC, that means every time someone finds a solution to a new block is rewarded with 12.5 BTC. This is equivalent to $63,350 (taking price per Bitcoin is $5100). This means that someone can earn 12.5 BTC every 10 minutes (average block time).
Many readers have the curiosity to know that is it necessary to hold or buy Bitcoin to start mining?
The Answer to this question is NO. This is not necessary to buy or hold any amount of Bitcoin to start mining. All you need is the mining hardware that is capable of doing millions of calculations per second and a good Internet connection. The process is very simple just plugin some wires and you are good to go.