The first step is to use Design of Experiment (DOE) to know the number of experimental runs should be performed and the parameters values for each run.

You need too to define precisely what reponse is of your interest to study. For example, surface roughness, geometry of the part, influence of Heat Affected Zone, and how the process variables affected each response.

Another important thing is the experimental evaluation, the experimental equipment to obtain a good work.

1. must be define the parameter

2. Conducts one of DoE methods like Taguchi or RSM...

3. Records the responses

4. Analysis the results

5. Conformation test