This paper discusses aspects of the procedures of the experimental validation of predictive computations conducted within the Center for Exascale Simulation of Plasma-Coupled Combustion (XPACC), funded by the Department of Energy, NNSA, and conducted at the University of Illinois. Aspects of the planning, communication, and execution of the validation are covered. Of particular note are lessons learned in defining the multi-physics prediction target, which serves as the specific goal for the simulation, and experiments conducted to provide a well-defined quantities of interest. To support the multi-physics efforts, several physics-targeted experiments and simulations are used to develop models, calibrate them when necessary, and validate aspects of the overall predictive simulations. A methodology of sharing information is also given, set up as specific tasks that insure individual-to-individual communication between computational personnel and the experimentalists designing experiments and making measurements. Key aspects of uncertainty quantification in the experimental research are discussed, which improves validation confidence in the full-scale predictive simulations.