Skills assessments can only be undertaken by the relevant assessing authority.
Assessing authorities and links to their websites are listed against occupations in the relevant
list of eligible skilled occupations.
You will need to have a skills assessment before you submit your EOI. If you are invited to apply for the visa and lodge a visa application, you will need to provide evidence that you held the skills assessment at the time you were invited.
More information is available about skills assessments and assessing authorities.