1. Dump the leftovers of your bi-weekly software engineering paycheck into buying ETH, BTC, or whichever altcoin is popular this week. It went up 5000% in the past, it's got to keep growing right?
2. Participate in an ICO and stock up on whatever platform token they're hawking. It's more profitable if you get in early due to some presale mechanism (hopefully here you aren't sending your hard-earned digital currency to a hacker's wallet). Sell these tokens about 4-5 days after the sale closes, before the hype dies down and the bagholders realize they're holding sand.
3. Even more profitable is kicking off your own ICO. Go through the checklist - fancy HTML5 theme that you can buy off of Themeforest and edit the HTML a bit for the landing page, create a Slack channel/Twitter account/subreddit, write a "whitepaper" that is easy enough for the shmucks you're targeting to understand, yet replete with enough pseudo-academic crypto jargon and irrelevant/unnecessary mathematical symbols to get the shmucks nodding their heads and pretending to understand how this particular algorithm/equation based on the "turing-complete ethereum blockchain" will "change the world" or "bank the unbanked" or, more importantly to them, appreciate 500x in value. Don't forget listing the members of your team and advisors, ideally with as much credential signalling as you can - "MIT," "Stanford," "Comp Sci Phd," "McKinsey," all work here, fake it till you make it and make sure you list Vitalik Buterin on your list of advisors just for that extra bit of technical legitimacy. Use centuries-old sales tactics to pitch your ICO - butter up your target audience's sense of superiority by emphasizing exclusivity - they're the only clever ones, they're the genius computer nerds who understand the 1000x potential of your algorithm, they're the ones that are breaking free of the shackles of regulated securities. Create a sense of urgency with a ticking timer on your landing page, a 24-hour window to buy your monopoly money, a subtle/not-so-subtle hint that the earlier you get in, the more you'll make.
4. You could always just put on your black hat and rob these extremely soft targets blind. The simpler the method, it seems, the better. Plus, there's absolutely no risk of ever being held accountable - that's the beauty of anonymous cryptocurrency!