Both English and Japanese versions are fully charted using standard knitting and/or crochet symbols.
Japanese version available here.
English version available here.

Materials: Japanese size 4/0 crochet hook (2.5mm)

Gauge information only says that one row of double crochet (US) should be 1cm tall.

Note: the pattern says that the entire doily is to be crocheted with 2 strands held together.