In this IMG activity you can assign your wage types to a wage type group.
All the wage types you want to use for special payments must be assigned to the wage type group 'Special payments'.
You should already have defined the wage types in the wage type catalog.
The standard R/3 system contains model wage types for special payments (e.g. vacation allowance, Christmas bonus) that are already assigned to the wage type group.
Check your wage types and add any new ones you require.