If I were you, I would start with at least $200 and split it up 4 ways into 4 different alt coins. $50 each. That can go a long way when you're starting out. Also, I always aim for a 6% increase. Wait for a spike then the gradual decline for a few daws and buy when its low, it will spike again. Afterall, the spikes that you see generally happen over the course of an hour. If your not watching you could miss it. Also, Its always good to diversify your portfolio. Take a look at Ripple (XRP) Currently trading at $0.25 per share. You could buy 200 shares with $50. By 2018, price has been expected to reach $3-$5 for ripple. (They're finally realeasing all the technology they've been working on and are having a conference with big bankers on October 16-18 for which they are looking for millions of dollars of investors.) Very Promising.

https://ripple.com/insights/news/announcing-swell-by-ripple/

TIPS: Make a separate twitter account. Any cryptocurrency's you're interested in. Follow them on twitter. Anytime some news comes out about an altcoin whether it be on their twitter or even better yet a credible news source article like fox news or cnbc, the price takes a spike on that altcoin. Keep up with social media, cryptocurrency is heavily affected my the media. Use subreddit /r/AltCoins. There is also a lot of good insider information on there, take it with caution though, a lot of people on there are just traders like you and me.