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How to crochet lace 
Work up a foundation chain. 
Attach crochet thread to your crochet hook using a slipknot, then work up 21 chain stitches. 
Check the " tips " section for information on making slip knots and chain stitches.
You can vary the length of this foundation chain, but make sure that your chains equal a number divisible by your intended groupings plus one. A standard grouping will be five stitches, so your chain count should be a multiple of five plus one extra : 21 , 26 , 31 , 36, etc.