Various Stages assuming you are applying for a 176 State Sponsored Permanent Resident Visa:

- Skills assessment by the relevant body (VETASSESS for me took 12 weeks) you need this before you can apply for state sponsorship
- State Sponsorship (our was approved in super fast time but check our the SA Immigration website for more up to date timeline)
- IELTS Test (if additional points are required) results took 2 weeks from test and you may have to wait several weeks until you can get booked into a test.
- 176 Visa Application, followed by medicals and police checks once you have been appointed a case officer. How long is a bit of string, this bit seems to vary quite a bit.

There is a useful post on this forum relating to timeline 'park your timelines here' which might give you more detail.