You’ll need to download and submit CASA Form 61- 4CT including all supporting documentation. There are bascically two options.
B1. After completion of your type rating course, you have the type rating endorsed on your foregn license.
B2. You undergo a type rating course provided by a foreign type rating training organisation using a foreign testing officer, after which, that testing officer fills in Form 61-4CT appendix 1 and 2 which in effect adds the rating on your CASA license.
I’ve done it both ways for two jet type ratings and Option B1 is by far the simplest option requiring less paperwork.