Present work is devoted to the problem of validity increasing of an experiment to detect the motion of a continuous medium by the waveguide method. The study attempts to optimize the experiment to find the optimal scheme for its installation. The target effect, the magnitude of which should be maximum, is the generalized reflection coefficient, which is influenced by both the Fresnel electromagnetic drag coefficient and the polarization plane rotation due to motion of the medium. The main optimization task is to determine the output parameters for the experiment for stable and reliable motion detection of a continuous medium in a waveguide. In this work, a heuristic analysis algorithm is used. Optimization factors: frequency of the signal at microwave, physical dimensions of objects, shape of the waveguide cross-section, linear velocity of the medium. ECAD PathWave EM Design (EMPro) 2021 was used to the experiment designing stages. Distilled water is the moving medium, which is not subject to optimization. The motion of a continuous medium is considered through its refined refractive index. The maximum magnitude of the target effect is observed for the topology with a rectangular waveguide and with a tube oriented along a wide wall at f = [9.3 ÷ 9.5] GHz. These values coincide with a good degree of accuracy with the already conducted experiments.