Gambling and MLM, HYips's and ref share are just methods to scam or play money for a slight chance to win and cloud mining is mostly the same as well, at least gambling has a clear odds and probabilities unlike these wanna-be scams.
Trading USD and BTC are the genuine ways to get profit from BTC depending on your skill in trading.
I do not have trading skills, couple days ago I opened one exchange site and all that was very confusing for me, numbers was changing like crazy, all those coins there, and how to know what will happen next? What to buy or when to sell, how can I develop my trading skills and where? I do not wish to throw my money on something that I do not understand, and from all reading on this forum I did not find where to start from.
Here on forum there is much more talking and bragging about trading then some practical steps that some newbie like me can understand.