Probably more than you need, but your question is very subjective as I have no idea what your financial situation is. Unless you start dumping into shit coins, my opinion is that its very unlikely you'd lose it. But that my opinion and not fact. I'd probably suggest you start with $100. Buy in and then transfer a small amount to a private wallet, destroy and recover your wallet. Transfer some to a friend after they've spotted you for lunch or a beer. Transfer to an exchange or two and then start buying / selling some bitcoin and altcoin. Sounds like a pain in the ass and jumping through hoops, but you'll learn a ton if you take the time to actually use it in various ways. While you're doing that, come back here and ask questions, skim the news headlines and look at some of the links others have posted in here for recommended sources.
Add to the discussion, speculate and ask questions. You'll dial it in.