How to give permission to another user on my git remote

Hi,

I have created one repository (but I'm not a root user on the server) like $ git init --bare

And I do push my changes locally to remote repo where I created. My friend also working the same repo, and he needs to push the changes on the same.

I tried by adding below line on the remote config file
[config]
        sharedRepository = true

Any help, how to do that.