You can add columns to your List by hitting this button top right.

Then selecting "Manage Columns".

From here you can add, delete and edit existing Columns. 

You can also choose whether you see your card image etc.

Press the + To create a new Column. 

You can choose from a variety of Column Types:

Field - you can choose a field from your Cards so if you update the list, it also updates the Card. Note: you need to set up your fields and link them to the relevant card category in order to edit them from the List. See What is a Field? for more info.

Rich Text - text just for your list (not on the Card itself)

Currency - a dollar value (you can edit the currency)

Number - a numerical value

Date - a date selector

True / False - a checkbox 

Filedrop - if you have created a file request from this Card, the unique filedrop link will automatically populate here.

Email - the default email address on the linked Card

Phone - the default phone number on the linked Card

Hit Save & Close when done.