Customize Templavoila new content element wizard

templavoila.wizards.newContentElement {
# Activate tabs for new content element wizard in TV
renderMode = tabs

wizardItems.common.elements.tx_custom_bigimage {
icon = Images/Bigimage.png
title = BG Image
description = BG Image
tt_content_defValues {
CType = tx_custom_bigimage
}
}
wizardItems.common.show := addToList(tx_custom_bigimage)
}

Where tx_custom_bigimage is custom content type. we need to add this code in pagetsconfig of root page.

Please refer to screenshot for more info.New content Element Wizard