investopedia is legit! trading everything has the same mechanincs;
develop your trading skills, research & find a Few alts with big market caps (
http://coinmarketcap.com), follow their trends for a while (said select a few coins so you can actually spend the time to follow them), dip your toes/test the water & start from there.
it's really not that complicated if you develop method & follow along.
I started out with them too. Learned the basics. But if you really want to learn trading, you should focus your attention on Technical Analysis. There are plenty of YouTube video's with information on that. If you are serious about it, pay a guru to learn you tricks.