As you can see from the colour wheel above, each colour hue can be highlighted (drybrushing) with the respective lighter colour shade (adding white paint to the original paint will give you the lighter variation). Please note that white is a strong colour and therefore you need to add white gradually until you reach the desired shade.
Some people prefer to use light yellow on yellow neighbouring hues (e.g. greens oranges and reds) , to achieve the desired lighter shade, since adding white to green will give you an emerald hue rather than a true green while adding white to red will result in pink rather than a red shade.
Experiment for yourself and decide the colours you want to work with.
