Tons of people earn money from btc futures. Check out the volume on 796 and okcoin, all that btc is going somewhere lol. If this weren't the case future markets wouldn't exist. Just look at a btc/usd chart zoomed out to a long term daily or 4 hour view. It's nearly all down for months on end. I can guarantee a lot of traders have made significant money shorting btc as they did buying in previous years. If you mean day trading well that is a bit more tricky with btc especially imho but long term trading is quite easy.
Here are 2 resources beginners may find quite helpful
http://www.babypips.com/school - This is a forex trading (global currency exchange) school with free lessons on the basics of trading. While the forex markets are not directly linked to futures the same basic principles can be applied.
http://forexfactory.com - Very active forex trading forum
Thanks, your links are helpful, especially the first link, I can learn trading knowledge there. I see your signature is 796 exchange link, I guess you earned lots of money there.