Off the top of my head for the common green uniform (which I assume you mean), that'd be GW Catachan Green with a dab of Baneblade Brown / Tallarn Sand. Might want to add a tiny bit of white to bring up the could a bit too. I'd avoid a light green instead of white as whilst the uniform itself is green, you'd be wanting to use browns for the tones to tie the models into the desert climate.