Afaik, the way you make money is buying into projects that have sufficient seriousness and hype backing them, when they are on a lull and their tokens are dirt cheap. Or buying them early into a pump that will grow and spread (as Ethereum did starting back in February). This purchasing opportunity can either be at the launch when not many people know about it (if it is a mined distribution) and/or after the initial pump such as after an ICO. Study the charts at coinmarketcap.com and see how all the altcoins have had these low price lulls.
Then you hold many of these and wait to sell them on the ensuing pump.
But you've got to be careful you don't pick duds that are mismanaged and disintegrate before being pumped.
And you need patience, meaning it can't really supply a steady income. Sometimes you'll be waiting a year or more for a payoff.
Also as another poster said, if we go into a severe bear market, then you the wait could be longer and your altcoins might die in that interim time.
The upside is you can probably average hundreds of percent gains per year on average. I'd prefer it to speculating on pink sheet stocks such as mining companies, because I can better gauge the potential of altcoins.
I haven't had time to analyze this one technologically, but its price and chart looks like it has the most potential to rise:
http://coinmarketcap.com/currencies/rise/ShadowCash and Vcash also look cheap, but I have doubts about what they can produce. Don't have a lot of confidence in their marketing and technological focus. ShadowCash perhaps a bit better than Vcash, although Monero's cryptographer found a flaw in their anonymity which raises some doubt since that is the main feature focus.
Actually after quickly browsing the top 100 altcoin's by marketcap, I don't really see much to get very excited about. Ethereum was the next big thing, but then they hard forked it and basically demonstrated that their programmable block chain concept is flawed.
As for Steem and Synereo, they are not on a lull and I have my doubts about their concepts:
https://bitcointalksearch.org/topic/m.15538471As for CounterParty, I recently explained it is flawed. Ditto all the decentralized file storage tokens, such as Storj, Sia, and MaidSafe are all irreparably flawed.