The custom sidebar is a useful feature in the Pesto WordPress theme which allows you to add more sidebars/widget areas into the widgets page.

Adding a Custom Sidebar

From the Navigate left menu go to Dashboard → Pesto → Footer Option

Click on Add a New Sidebar and type Page Widget Area

Click on the Save Settings button.

Showing Custom Sidebars Widgets.

From the Navigate left menu go to Dashboard → Appearance → Widgets

To Add Any Widget Area sidebar