I need the code used by shopify to integrate a tracking code

[Inotex]

Hi, 

I want to integrate an tracking code in shopify Additional scripts but I have a problem. The app needs codes from shopify to identify order number and others to track the website right. 

These are the lines that I need to change with shopify code to work:

• __ADD_SALE_VALUE__ - replace it with the total value of the sale without taxes and delivery costs.
• __ADD_DESCRIPTION__ - replace it with an informative message about the transaction (e.g. what products have been sold).
• __ADD_TRANSACTION_ID__ - replace it with an unique id that will identify the transaction.

Can someone help me with the shopify codes? I think for TRANSACTION ID shopify use: {orderName}