DOE is a more formal approach to learn about the impact of process parameters on a specific characteristic of the product. It can be applied to any process and they say that having only a basic knowledge about what are the major parameters and their range will suffice to perform DOE. 

This is not completely thru. The more detailed information the one has about the process parameters, about other models for the same or similar process, about the physical or chemical processes taking place the better  choice of experimental plan.  Materials, Metallurgical and Chemical Engineer who are  knowledgeable about materials processing and specifics handle DOE for processes for/ with materials better then other professionals. The following are the steps of DOE

1. Learn more about your process and process parameters from the technical literature in order to be able to list and rank them them with their ranges of change and importance and to also indicate the major parameters. The more information you have , the better your decision about the plan /experimental matrix

2. Estimate the the number of experiments based on the required accuracy and costs. Trades-off with the model accuracy reduce the experimental work and costs but affect negatively the accuracy. The higher model precision you want to get, the more investments for experiments ( see samples of matrices below > ) Select a DOE plan while bear in mind that:

   • A full factorial requires the highest number of experiments and provides the highest precision of the model. Check with the catalog about the Number of experiments or

N= L^f    where N- # of experiments L- # of levels, f- # of factors ( See samples of matrix below > )

• A fractional factorial requires less experiment but is also gives a less accurate model ( See samples of matrix below > )

•  The replication is important, 3 trials at the same process parameters settings is recommended

3. Have the matrix of the experiment selected, plan the physical experiment. Keep your experiment in control. Make sure you change only parameters required. Take materials/parts from one lot or package. Use the same measurement techniques and devices for the entire experiment. Carefully record all data including for all the parameters, make  notes about the environmental conditions.

4. Analyze the results 1-st from the matrix of the plan by factor e.g. by column evaluating the impact of each parameter on the output /response. Using simple addition or subtraction you can find out the factors of highest impact. Design graphs displaying results. Make conclusions about the parameters impact. Use this knowledge to set up your parameters and an experiment with the best output.