Go to Insurance references :

Double-click (or modify button) on the LAA line.

Fill in all the fields. 

If it's a compatible Swissdec insurance, you can click on Load a profile and choose one :

Check the insurance contract carefully to see if it mentions different codes. 

Then go to Details of contracts :  

Double-click (or modify button) on the line.

Indicate the description (If there is only one category of insurance, you can enter All employees. This information is purely internal for the user).

Indicate the annual limit /12. (Currently 148'200.--/12 = 12'350.--).

Indicate the employer's AAP rate.

Indicate the AANP rate at which it is paid (employee, employer, both).

Create as many lines as needed. (More than one is uncommon)

Go to Settings, Salary items and check in the Computation elements tab that the contract matches:

For more details about setting up the items,

See here for LAAP

See here for the LAANP

To see how to manage it at the employee level, see here.