When calculating C1, subtract the blank from your reading and multiple by the dilution factor
Example: C1 = (1:8 OD600 - blank OD600) x 8 = (0.195 - 0.042) x 8 = 0.153 x 8 = 1.224
Example: (C1)(V1) = (C2)(V2)
(1.224)(x) = (0.1)(1000 μL)
x = 100/1.224 = 82 μL culture
Add 82 μL of culture to 918 μL media for a total volume of 1000 μL