I'm getting ready to do mine again and went back and dug up a picture I put together last time I did this. Seems a bit archaic, sure, but the spacing ends up "perfect", and meets the dimensions specified in the above diagram. It's just a lot easier to do this way in my opinion, since you don't have to deal with keeping a tape measurer in place, etc. YMMV.
Where stated, "
n full diamonds showing" means at least
n full diamonds, but not
n + 1. For example, "4 full diamonds showing" might mean that you actually see 4 full ones and part of a 5th one, but not 5 full ones.
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