Varnish on WordPress: How to bypass it for logged in Administrator?

where should i paste this code? Or what is the command to stop temporary varnish cache when i am developing website & looking for changes.

You can configure Varnish to disable caching for a specific IP using something like:

acl passem {
        "your.ip.address";
}

sub vcl_recv {
  #(..)
  if (client.ip ~ passem) {
    return(pass);
  }
  #(..)

}