Installation Guide - protegeproject/cellfie-plugin GitHub Wiki
For Protege v.5.0.0 Beta 17 and earlier: Download Cellfie plug-in 1.0.0 Beta 1 and copy the .jar file in the plugins directory that is in your local Protege installation directory. Then (re-)start Protege.
For Protege v.5.0.0 Beta 18 and later: Cellfie should come bundled with Protege.
If Cellfie is installed properly under the Tools menu you should see a menu item called Create axioms from Excel workbook..., which you can use to open Cellfie.