I draw it by hand on the metal...Chinese white or transfer wax with 9H pencil...the old fashioned way
Generally the only transfers I do are with wax and tape OR I will trace with pencil and tracing paper artwork, reduce to size, then transfer using tracing paper to get pencil lead to the part
Occasionally (rarely) I will use tom white magic transfer for complicated subjects or subjects that have to be 100% accurate to look right, ie, a celtic knot, logo, signature....