I sold mine at 1020$. I guess I was a bit hasty about my decision. I just couldn't risk the possibily of a huge dump from 1000's to 800's. A dump like that recently happened and I was mad at myself for not selling above 1000's. So i did it this time.

If you can't handle the risk/votality, or you need money then sell your Bitcoin to prevent you selling it at lower price. However, if you can handle it and you used that money to get profit without doing something but to wait, then hold your Bitcoin. Bitcoin has a future to rise up more since it's being introduce or it is currently reviewing buy government to use it as decentralized mode of payment that would be endorsed/support by them.
There is no specific time of buying and selling. Everyone have different goal to reach the price where they want to sell their coins and how much stack they will spend. Personally i used doubling price strategy, which i sell on the price where i buy it with double amount, do repeatly, but there are also have an obstacles, where the price move to a specific point or its suitable for me than I decide when we want to buy/sell.
But, As specifically of bitcoin, i think its time is good to hold your bitcoin for the next year and i will selling my bitcoin to the next year when bitcoin price increase to 25000$ then i will sell it and then i again buy bitcoin in high amount with low price and i will get a big profit in good amount to the next year.