Everyone is different, so it is best to come up with your own unique plan before entering a trade.
For instance you may want to have a level at which you will sell the stock if it is profitable and a level which you would sell and cut your losses short if it is not profitable.
I like to use technical analysis to tell me where the key levels of Support and Resistance are that way I know if it breaks support it is most likely heading lower and if it breaks Resistance it is most likely heading higher.
However you want to approach it make sure that you have a plan BEFORE you enter the position. This will save you from running around panicking trying to figure out what to do in the future. “If you fail to plan you plan to fail”