Select the desired slot type in the drop-down list of existing slot types. The list contains all slot types that were created client-specifically. In case the required slot type doesn't exist please select any slot type and save the slot - you may assign a new slot type later, see 3.1 Dialog Edit Slot Types.
Notice:
On assigning a slot type to a slot all default values of the slot type which are not NULL will be transferred to the slot (see message).