From the pattern: This doily made in size 30 thread measures 10 inces dia., and requires about 150 yards thread, for a larger doily may be made in heavier thread, use hook which works well with size thread used … also pretty in colors

A doily in 23 rounds features
pinwheel center using dc
chain in chain
tr crowns
double treble crochet clusters
3 ch and 4 ch picots