I have been running through most of the discussions on SDN. And figured out that beginners always try to create a copy or Z of standard Fiori applications.
It is not recommended of you to copy standard fiori apps,but its certainly feasible.
Let me take you to a step by step guide on how to do it.
Step1: Download the code from NW portal by executing report /UI5/UI5_REPOSITORY_LOAD in SE38.
You can find the steps in various extension guides/blogs etc. Or follow this link Extending a Fiori App – Simple Use case – Part 2
Step2: Create a application project in Eclipse.(You should have already setup your development environment before this).
Step3: Copy your downloaded code to webcontent folder of your application project. Your folder structure should look like this.
Step4: Change the namespace of Standard Application.
Open Component.js file. You will see that the namespace which SAP follows for this application is hcm.mgr.approve.timesheet .
I am changing this to zhcm.mgr.approve.timesheet.cust . Do it for all the files.
Step5: That’s it. You are done!. You can check the application locally first and than transfer to NW.
Refer this link Extending a Fiori App – Simple Use case – Part 3
Make sure you use below parameter value