Consider the following guidelines when you define the design.
The size of the design should be adequate
The sample size and power should be desirable for a practically important effect size. To evaluate the design, use Stat > Power and Sample Size > General Full Factorial Design.
The design should have 2 to 15 factors
If you have only one factor, you can use One-Way
ANOVA without defining the design.
The run order should be randomized for data collection
If the worksheet contains a column that contains the run order, you can specify that column when you define the design. Otherwise, you can randomize the design after you define the design with Stat > DOE > Modify Design.