Beginner trying to make puzzles

[Merdock]

I have had much fun solving sudoku puzzles, and the other day I had an idea for one. Unfortunately, I have never made a puzzle before. When I was reviewing the "Instructions for setting puzzles" page on Logic-Masters, it says that the sudoku must be inserted in HTML format, with a link that seemingly goes to a tutorial page. However, it appears that that page can not be reached. Is there a new tutorial page, or a location that you would recommend beginners go to for creating puzzles? Also, is there a way that you recommend people check that there is only one solution beyond just attempting to solve it ourselves. Especially as this would be my first puzzle, I don't know how well I trust myself that I didn't make a mistake.