Ratios for making Dashi from Kombu and Katsuobushi
Measure both with weight, start with a ratio you find to be tasty and produce varying kombu to katsuobushi ratios in equal steps, preferably 3 or 5 variations in small batches. Make sure to keep liquids, temperature etc. as much of a constant as you can.

Taste all, make notes and have others taste test them as well.
This process should be repeated each time the source of your katsuobushio or kombu changes.

Unless you live in Japan, consistency may be hit and miss.