Any light yellowish green or even Vallejo 'Iraqui Sand' mixed with a little green will do. Now the schmocks base color is painted on using Foundry 'Moss 29A'. Of course you can still use any kind of base coat you're used to. It gives a nice flat finish when applied by airbrush and can be brushed on to touch up areas not covered with the airbrush. For basecoating 'Acrylic-Polyurethane Black Surface Primer' by Vallejo is used. The figure used is a German Fallschirmjäger from Warlord Games. When referred to Vallejo colours go for the Vallejo Model Colour line of products.
Also remember the figure shown is about 1/3 as high in real life as on the pictures. Please remember I'm not doing a 1:1 replica of the original pattern but a version suited to be viewed at gaming distance. A few people have asked me to do a quick tutorial about my approach to WWII splinter pattern or officially 'Buntfarbenmuster 31'.