The shopping cart allows you to add variants (options) to a product like colour and size.
If you have multiple variations to add to a product (e.g., colour AND size) then you will need to think about how you want to keep track of the combinations of stock. You can either keep track of the stock at the product level and ignore the options chosen, or keep track of it based on pairs of the combinations chosen (e.g., colour and size, length and width, colour and weight, etc.).
The process for adding options is:
1) Create the Variant option (e.g., size or colour), and add its options
2) Create the Product that will have the options
3) Assign the Options to the product
4) Tell the cart whether to keep track of stock on the variant option pairs or not.
These steps are covered below.
1) Create the variant option
Variants are first created in the store so they can be added to products. This approach gives you the flexibility to add the same variation set to multiple products easily.
To create an option variation:
1. Go to Products > Options/Variants from the main menu in your administration panel. A list of the existing product options will be given. 
2. Click the + button to add a new option/variant
3. Complete the create an option screen. 
Here is a short description of what the fields mean:
Option Name - the name of the thing that you are creating (e.g., size, colour, texture, weight, type, etc.)
Display Name - how the name of the thing that you are creating will be shown on the checkout to customers
Private Note - add a descriptor to the type if you have multiple things of the same type. E.g., if you have different product variations for colour you can use this field to help you tell the difference between them when you go to add them to a product. Otherwise you'd have a big long list of items that all said Colour.
Type - how you want the option to be displayed to customers on the product screen - a dropdown box ("select") is the most common, but you might want to have a type in field (if customers can provide wording for a personalised item, or can upload a file (e.g., artwork for printing))
Sort Order - assign a priority number to this field to sort multiple options on the same product. E.g., If you had colour and size and wanted colour to appear first, then give colour a sort order of 1 and size a sort order of 2. The cart puts the sort order values into ascending order on the product screen
Option Values - these are the variations that your customer can choose from (e.g., Red, Green, Blue, Black, .............). You can add these and assign an image to them.
When you're finished, just click the "save" icon to return to the options/variants list screen. If you want to save as you go, click on the tick button which means "save but keep working on this screen".
2) Create the product that will have the option assigned to it
Assuming you've already set up your categories, to create a new product go to Products > View Products from the side menus and then click the + button to add a product. For detailed information about the other aspects of adding a product see the other Products Articles in the Ozcart knowledge base, or the articles on adding a category or adding a product for the basic steps in completing the process.
With the basic details of the product added, you can go to the Options/Variants tab on the product creation screen.
You will then be able to type the name of the option you created for an auto-complete box to drop down with the matches. This is where the private note is useful, because the private note will be appended to the list of names shown so you can choose the right variant to add.
When you select an option, it opens the Options/Variants editing screen, where you can put in the details of the Variant.
The fields are:
Required - must the customer select a variant from this option in order to checkout?
Option Pair - If you are using option pairs to manage your stock, you can select the pair that this item goes with. To prevent the cart going around in circles when calculating stock, you set up the first item in the pair with NO pair and no stock management, and only add the link to the SECOND item in the pair.
Here's a screenshot describing how Option Pair works.
In the example above, the Turquoise colour is dependant upon the Size and the values of Size (Large, Medium, Small). On your product page, on the storefront, if you select Medium or Small, you can combine these sizes with the Turquoise colour. If you select Large, you cannot select the Turquoise colour as it will disappear. It means that the Large size does not come in the Turquoise colour but only Medium and Small sizes do. You can add more colours and combine them with different sizes. This works with any other type of option, variant, and value that you can think of.
If you don't add an Option Pair, then the option/variant will show up as intended without being affected by anything.
In the table underneath the first two dropdowns:
Variant Value - the specific value of the variant shown to the customer (e.g., Turquoise, Blue, Pink, etc)
Quantity - if this is a single option and you want to keep track of the stock, put the stock quantity into this field. If this is the first item in a combination pair, then leave this blank. If this is the second item of a combination pair, and you are managing stock for the pair then enter the quantity here.
Option Pair - if this is the matching part of a combination pair then select it. The choices will change depending on what you have chosen as the variant pair.
Subtract Stock - if you manage stock on this option or combination, then select Yes here. Remember if this is the first item in a managed pair, choose No, to prevent the cart going in circles at calculation time
Price - enter the additional cost for choosing this option. E.g., if the option is gold leaf edging and you charge an extra 75c per quantity for this item then put 0.75 into the price or price + gst box (the other box gets calculated automatically - you only need to enter one of the other).
Points - if the customer gets a rewards points bonus for choosing this option, then select it here
Weight - if choosing this option adds to the overall shipping weight of your package then enter it here. If you are using the Australia Post automatic calculator this field will be important. The weight should be entered in kilos, so 89grams is entered as 0.089, 920g is entered as 0.920 etc.
SKU - if this option or combination pair has an SKU then entered it here - it will be shown on the cart page at checkout.
Note for v2/v3/v4 customers moving to this platform:
For customers moving to this version from the v2, v3 and v4 platforms, this approach to creating options was previously called "Global Options" being added as a "template". i.e. variants are created and then assigned to the products. They do not stay linked to the original options, giving you the flexibility of adding the variants to multiple products
What if more than two variants make up a combination?
The cart only allows you to pair combinations to keep track of stock that way, so you would either need a separate product for a third dimension (e.g., Large Sculpture (colour/texture combination choice), Medium Sculpture (colour/texture combination choice), Small Sculpture (colour/texture combination choice), or to keep track of stock combinations outside of the shopping cart.
