Click on "Machines/Methods", then "Edit Machines/Methods".
A list of existing machines/methods for which you have edit access are displayed in a table.
In the "Actions" column of the table click the dropdown menu next to the "Edit" button in the row of the machine/method you wish to delete and select the option "Delete". To filter the list to locate a particular machine/method, type keywords in the table search bar.
Select "OK" in the popup window when prompted to confirm the deletion of the machine/method.