Provide managed path under which you want all personal sites to be created. This managed path will be used to form the URL ...

Provide managed path under which you want all personal sites to be created. This managed path will be used to form the URL for My Sites on the same Web Application as the My Site Host.

Example: http://<My Site Host Web Application Path>/<My Site Managed Path>/<Site Naming Format> will be the URL for the personal site for a user.