Models are needed to create types of cards.
For a quick start, we recommend (if they are not yet created) creating two models of cards:
1. Standard model with no value
2. Standard model with value (value allows you to introduce a number in your cards so as you can for example quantify the value of an opportunity, business, etc.)
3. Create one type of card using the model Standard model with no value.
This video explains how to create card models and types.
Models and Card types
Understanding the difference between Models and Card types:
A model is used as a template to create several types of cards that will need the same custom fields. A model of card allows for example to create custom fields. Those custom fields will be replicated in any type of card that uses that model.