In Zotero, select the records you wish to export.

Right-click on the selection and from the menu bar select Export selected items.

Choose to export in RIS format.

A file will be created called Exported Items.ris. Save this file to your computer.  You can rename it if you like, but keep the ris extension.

Log into RefWorks and from the References menu select Import.

Select RIS Format as your Data Source  and  Database.

Browse for the .ris file you saved to your computer and click Import.

Your references will appear in the Last Imported folder