Not aware of any trick, but if you find one, I'd love to hear it! This is only my second project. I've no idea why your pieces don't match. If you've done it according to the guidelines - i.e. sewn on the sewing lines (not the cutting lines) and used 1/4" seams, it should.
I'm now joining my 'Raindrops' ready to add the navy backing and they seem to match OK so far. I took all the papers off, but I know some people only peel back to the 1/4" for joining and remove at the end. I think I'm going to have to flip some seams too. Hope you work it out!
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