For color effects or color balance adjustments (does not fit in the diffuser for the SB600, Eyelead diffuser for the Nikon SB600), the filters are simply inserted in the diffuser.
The yellow and red filters are ideal for warming artificial lighting, the blue is suitable for high Kelvin values, for example when shooting outdoors at noon. The green filter colors the flash light very close to the color of the fluorescent light.
