I used some reference images in orthographic axis to build the first surfaces, to have the main volume.
It took me few trials to have the right dimensions but I could then build the rest of the car without scale problems. I was also helping myself with real pictures to better evaluate surfaces.
I closed the main shape, keeping sharp edges for a further application of fillets. I then detailed the model, using alignment properties, trims on surfaces with different reference axis and other tools in order to get as close possible as the real car.
I allocated a lot of time on curvature verification all along the modelling to keep an eye on homogeneity and continuitivity.
I learned the verification of normal direction for surfaces, and groups allocation for lighting. It allowed me to export correctly the model in Vred and assign easily the textures.