Bitcoin is money, and like anything that has high value earning it is not an easy thing especially if we know bitcoin does not have as many ways of being earned as fiat does, so my advice is to stop thinking it is easy to earn bitcoin, you need to work long and hard.
And with that mindset, it's the fact that earning bitcoin isn't that easy for a person that doesn't have broad knowledge when it comes to bitcoin. But if you are aware of what you are doing and probably you are making decent amount with your source that is going to give you a nice income. You can just trade with alt coins just like what everyone is doing now.
Trading altcoins is the best way to increase your bitcoins in the wallet and most of the people are doing the same at a moment as the altcoin market looks promising and if you invest in a right coin at a right time after doing a good research then you will be making some really good profits in quick time and apart from trading there is no other ways to increase your bitcoins in quick time.
Gambling is not recommended.