I guess that most of us here are puzzle enthusiasts but very much amateurs that aren't going to challenge the world's best solvers any time soon!
But for those that do want to get into puzzle competitions and contests, which I've thought of doing a couple of times (but never done!) there are various suggestions I can make to help:
First, decide if you want to be a puzzle specialist or a generalist. For instance there are lots of competitions on a single puzzle type, such as sudoku or crosswords, but there are also competitions covering a range of all logic puzzles. So decide what you want to do first.
Second, practice, practice, practice. Go to competition puzzle sites and download samples of past puzzles. There are people who create the sorts of puzzles that will appear in competitions. If you are doing a single puzzle it's a bit easier - practice loads of crosswords, or loads of sudoku.
Then find the championships - for sudoku and crosswords there is a Times championship each year, and when you feel confident enough you might want to apply for these. Lots of people who compete in these have blogs and sample puzzles and share hints and tips, so you can find out the sort of solving times they have to benchmark whereabouts you might come: if you are miles slower then you would enter just for the fun, but if you are within 10% or so of their solving times then you know you have a real change.
Has anyone ever entered puzzle competitions? Be interested to know!
How to solve a Sandwich Sudoku If you know the rules of sandwich sudoku but aren't sure how best to tackle a puzzle, this video walks through a puzzle and how to solve it to get you started. Highly recommended, as it's a really fun puzzle type to solve...
If you've never solved a sandwich sudoku, then a 6x6 puzzle is a good place to start. You can have a go at solving the puzzle featured in the video here: 6x6 Sandwich Sudoku Puzzle Online
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