Go to ird.govt.nz and select myIR login (top right)
NB: If you don't have an IRD login, you will need to register for one by clicking the Not yet registered? link at the bottom
Once logged in, select the Income Tax box which will take you into the next screen where you need to select the Periods tab
Click on the year that you are wanting to access the earnings information for
Then, on the right-hand signed, you should see a link to Income Tax Return, click this and then Print Return
This will then take you into your filing confirmation which is your summary of earnings declared to IRD
In order to print or save the return, you can select either of the below buttons (top right of the screen)
And that's it!