Comprehensive guide to sudoku on YouTube
My friend Sudoku Swami (I like to call him "Mr. Swami") is an expert in solving sudoku puzzles using candidates. He has a video series on YouTube that will teach you how to solve even the hardest puzzles with ease.
I have given him some of the hardest puzzles I have solved on my YouTube channel and he has solved them in just a few minutes using the techniques you can learn on his YouTube channel.
Mr. Swami has one of the most comprehensive (if not the most comprehensive) tutorials on YouTube about sudoku and how to master it. Mr. Swami's videos teach all of the details you need to master sudoku. You can learn a lot from him and greatly improve your understanding of sudoku.
I recommend that you subscribe to his channel.
Sudoku - the puzzle that addicts