When you want to group the incident list by default(i.e on opening the list view from a module), you can achieve it by editing the module's Link Type field.
1)In the nav bar, search for System definition --> Modules and select it.
2)In the list, filter the table(example: Incident) and the module title(example: All) where you want to group the list and open it
3)Under Link Type tab, select URL (from Arguments:) in the Link Type field
4)In the Arguments field, paste the below value
This will group the incident table list by State for 'Incident --> All' module