Go to Seller Admin > View/Edit/Delete Products:
Select an existing tangible product of yours and click Edit;
On the first screen, if Shipping/Buyer's Address is not checked there, tick that box;
Shipping Options:
- Weight: [enter the per-unit weight of the product in Grams];
Click Next until you can Submit to save settings;
Repeat this for all your tangible goods;
When adding new tangible products, remember to enable Shipping/Buyer's Address.
Go to Seller Admin > Cart Shipping Settings and set up the following:
Shipping Origin: select your country and enter your zipcode (if you're outside the US, just enter any 5-digit number);
Shipping Destinations: if you will only ship to certain countries, select them in the list, or otherwise select nothing for Worldwide shipping;
Weight Unit Preference: Grams;
Leave all other settings blank or 0.00;
Click Next to save settings and proceed to the Shipping Rules screen.
In the Existing Shipping Rules menu, select and Delete any Rules you may have saved there.
Set up your first Shipping Rule for Domestic shipping up to 500g:
Shipping Rate Calculator: Flat;
Shipping Amount: 6.00;
Country: Australia;
Max. Weight: 500;
Click Submit to save the Rule.
Add another Rule for orders of 501g to 3kg:
Shipping Rate Calculator: Flat;
Shipping Amount: 9.90;
Country: Australia;
Min. Weight: 501;
Max. Weight: 3000;
Click Submit to save the Rule.
Note this will leave orders over 3kg unable to check out (since no Shipping Rule would apply in that case), so you might want to add another Rule for 3kg and up Domestic shipping if you expect any orders of that size.
If you will ship Internationally at a different rate, repeat steps like the above to create additional Rules for the appropriate weight ranges, but select Country: All Countries (i.e., the rest of your Shipping Destination countries).
Click Back to Admin, and you're done!
