Puzzle InstructionsMaybe one day I'll get around to writing versions of rules to puzzles with a nice tutorial element to them.
However, a pretty good version exists already, courtesy of nikoli. See below for direct links.
Akari - Fillomino - Hashi - Heyawake - Kakuro - Masyu - Numberlink - Nurikabe - Shikaku - Slalom - Slitherlink - Sudoku (Maybe you know these already) - Yajilin
Another great source is courtesy of the Grandmaster Puzzles blog, The Art of Puzzles. That said, finding the rules to puzzles is a bit harder work there. You'll typically have to find a post with that puzzle first, and then on it will be a link to the rules. I'm not going to do that for you.
Difficulty RatingsUp until August 2020, I published puzzles under an easy / medium / hard rating system.
Currently, I am using a 10 point scale to grade difficulty, roughly calibrated to these descriptions. Please note that your experience may vary from these ratings, as they generally penalise solving techniques that use uniqueness, bifurcation or intuition/visualisation.