Invest in altcoins. Watch the market for a couple of months then take the plunge.
Worst advice on this thread.
Most people lose out investing in altcoin over the long term. Only take 1-2 scams to lose most of your bitcoin holding.
It works if you're willing to put in the research and learn the indicators which reveal likely scams. You don't need to invest in many projects to get a large return. Just be patient, learn the technology, understand the market, and make sure you understand the supply/emission schedule.
There are quite a few people making a living trading alts. There are also people who use it as a sort of casino. But it's certainly not impossible to make a profit.