Procedure for creating Euclid VIS-simulated galaxies from the generator output and their parametric double-Sérsic counterparts. First, the generated images are deconvolved by their Gaussian training PSF, and then a shear is applied, after which they are convolved with the Euclid PSF from Appendix C. Next, the galaxies are re-binned to the correct pixel scale of $l=0\stackrel{″}{.}1$. Finally, the total image flux is rescaled according to an apparent magnitude following Eq. (28) and CCD noise is added using the GalSim.CCDNoise tool.