Support and resistance lines are the best so far to identify new trend and its direction. When price breaks out through the lines, it is likely that a new trend is born. You can draw S/R lines manually, and you can even have ones drawn automatically by Super S/R indicator (download from Indicators forum).
There're many ways to profitable exits. One is to exit after x hours/mins. Another is a take profit order of x pips. Ideally you'd want to exit right when the price is reversing. Look for a new trend that could go against your position and close it right away.