In such an unstable market, any decision to sell or buy can be counterproductive, especially if moved by the intention of increasing our assets. For example, to increase my amount of LEO, I sell my coins when the price is high and I buy them when the price falls. It seems easy but the market almost never reflects our projection, indeed it often seems to move in the opposite direction: when we sell the price goes up and when we buy the price goes down. Who has never happened to? It is difficult to predict the market trend if we are not large whales able to manipulate it.
The best strategy, it seems absurd, is to do absolutely nothing, set yourself a goal and move only when it is achieved. Bitcoin example: those who bought Bitcoin in 2017 at 15k or 20k and did it only for trading, if they are not a professional, they have certainly sold at a lower price, for fear of losing all the invested capital, having no goal to long term. A mistake that cost him dearly and that he would have avoided if only he had believed more in his investment, given that today BTC is close to 60k dollars.
So I am not at all impressed to have bought CUB at $ 3 and today to see it slide to $ 2, I will never sell my coins for fear of losing my capital, even if the short-term decline continues. It is enough to read the latest announcement by 
The bad name of the crypto world is that of making easy money, many really believe in it, even I was among those a few years ago, but then I understood and studied a little, and I didn't run away, I stayed to learn and I understood better how to invest and on what. Nobody here has the magic sphere but there are only possibilities and choices to be made. I believe that the choice to do nothing, after having invested in a carefully chosen project, no shitcoin, is the best thing that a user who is not an expert in trading but with clear ideas can do.
I hope that my advice can be impressed on all new subscribers or new users who are entering the world of cryptocurrencies for the first time. Do not invest anything at the beginning, study the fundamentals of the blockchain well, what it is and why everyone would like to invest: if the answer is only money, then get out as soon as possible because you will lose your savings. When my friends ask me what they should invest in, I tell them before reading the Bitcoin White Paper, it is the cryptocurrency bible and explains why Nastoshi Sakamoto one day decided to create and mine Bitcoin, the thirst for money in 2009 it was certainly not his priority