I have been told by people working in $200k+/$300k+ SWE jobs to look up at the answers and just be able to regurgitate something along the lines of the Grind 75 answers as a first step.
As a next step - even within these 75 questions, Grind 75's eighth answer and fourteenth answer are answered essentially the same way, as are other questions in there. So the next step would be to see these patterns (binary search, priority queues, sliding window, backtracking) and how to answer them, and then be able to solve them in slightly novel problems (in the more complex questions I understand one might run into more than one of these patterns).
This is a good way to do it IMO. Though I would say you don't want to just memorize answers; you want to fully understand them. Also, paying for LeetCode premium is very helpful since their official solutions are easy to understand and explain how you might arrive at these solutions yourself.
As a next step - even within these 75 questions, Grind 75's eighth answer and fourteenth answer are answered essentially the same way, as are other questions in there. So the next step would be to see these patterns (binary search, priority queues, sliding window, backtracking) and how to answer them, and then be able to solve them in slightly novel problems (in the more complex questions I understand one might run into more than one of these patterns).