I sell tiny fractions at many different points on the way up, and buy tiny fractions at many different points on the way down. As I read elsewhere recently: Biggest noob mistake is putting everything on one (or two) trades.

I also keep a spreadsheet of all my trades, to keep very close eye on my average buy-in price over set periods. So I know at a glance if I'm 14% up, or 82% down.

I use the same strategy on LTC/BTC, LTC/USD, NMC/BTC, NVC/USD, XPM/BTC.