Holding too tight

In my effort to protect a $200 profit, I raised my SL only to have it trigger and then the stock continues to go up. I rarely go back into a stock that I've sold with a SL. I know the SL is used to protect, however, I've missed some gains by having it too tight.

How do I combat this:
1. move stop up and sell half of shares to lock in gains
2. keep watching the stock after the SL triggered to get back in if when the price stabilizes