Not sure how to edit your theme? Read this article first:
​http://support.limoniapps.com/setting-up-dynamic-pricing/editing-your-theme

A drawer cart can typically be found in a file with the name drawer cart, ajax cart or mini cart in it.

The changes required for a drawer cart are almost identical to the ones documented for a normal cart here: http://support.limoniapps.com/setting-up-dynamic-pricing/cart-page/set-up-dynamic-pricing-on-the-cart

There are two differences:

There is one exception, on the root you'll need limoniapps-discountninja-drawercart-root instead of limoniapps-discountninja-cart-root.

On the drawer cart the subtotal price must be marked. If the subtotal price is not marked the app does not successfully detect the drawer cart.

Note that you may need to find the JavaScript file that prepares the data for the template to find the name of the variable or create the variable.