Toggling Outline Style

I am using Writer in Version: 7.5.7.1 (X86_64) and attempting to use an outline style. I have read through various help descriptions but cannot toggle the outline style. The style toolbar or side bar does not have a separate tab/selection for outline style. I have read that this is may be established through the use of Headings but have not been able to establish how this could be done. Any suggestions would be appreciated, Thanks.

Thank you for the reply and clarification