I would like to share a few things that helped me and is helping me. It might be helpful to some and not all. You may use it for your own self.
The HammerHead Technique.
You know the hammer doesn't hit the nail most times at first hit. It takes a few hits to put in the spot.
Same way certain concepts don't strike immediately, it needs revision or time or different way to understand it better.
The hammer head technique is to hit the concept with different sources, timed or spaced intervals and giving time between each revision until you get the concept.
When you get stuck you can try a different source to understand what you did not understand Then revisit the primary source again to see how much you have understood. You may give time between each revision to understand how much you learnt.
The TimeBomb Scene.This should be helpful in interviews. The timebomb scene is knowing that a clock is ticking and we have to act fast. Practice it to master how we react to a pressure scenario. Know what puts you under pressure and practice focusing on the situation at hand.
How to use it:
TPP technique - Think - Present - Polish.
Put up a timer and then practice the following:
'T'hink - Read the problem for the first time. This is important to see how fast or slow we read a problem. We understand what scenario has been put in front of us.
'P'resent - After you have thought what needs to be solved. You need to present how to solve the question. Do you need to use a function, if condition or break or need 5-6 variables or what is needed.
'P'olish - You write it down and make it work.
This process is of actually writing down the code. Correcting any syntax and checking if variables names are consistent and not in different cases.
Figure out where you are stuck and practice improving in that.
In Thinking we need to see how we read the problem and how different problems are written.
In Presenting we need to go through different approaches used to solve a problem.
In Polishing we need to actually write code to see how we put it out on the editor.
Once you figure out a pattern on how you go through the process you can deal with it better. You may also have a variable name wrong or some letter maybe in upper lower case and done unintentionally. Check for variable names.