start trading on an exchange or buy hardware and start mining 
Basically this..Ways to earn Bitcoin:
1. Trading
2. Mining
3. Getting a job that pays you in Bitcoin
4. Earn more $ and buy more Bitcoin with it
You may add your list bounty campaign, if you give some effort for bounty campaigns you can win something good. But i offer everybody to hodl coins which you gain from bounty campaigns
Yes, that's right. And by the way, now there are a lot of websites, that are specialized in bounties.