But it is not an easy thing to just know you need to buy low and sell high. How can you execute that if you don't know when the price of the market will be considered low now and later on it will go up?
When the bitcoin price drops below 60k, it is a buying signal and if it further 55k and so on, you should definitely be buying. If it continues to drop, ration your available funds into different buying levels as the price continues to drop. Follow this till you are out of cash to spend on buying from your allotment.
Now the selling starts when you start to break even from each level. Keep the least price of buying held back for the maximum profit form that and you can start selling the rest of the positions.
This is one summary of how to apply a buy low sell high method, there are variations to this and you can modify this as per your funds and needs.