<?php /* we're using php comments to make sure it is commented completely! this is the code snippet to assign the extra fields array to the variable called $custom */ ?>
	<?php $custom = $this->item->extra_fields; ?>
<?php /* this is the if statement to show a block of code only if the first custom field is not empty */ ?>
	<?php if(!empty($custom[0]->value)):?>
		This is the code or text to show only if the first custom field is not empty. To actually output the field in here, you would add it like this:
		<?php echo $custom[0]->value;?>
	<?php endif;?>
<?php /* to make this work for any other field, just change the number in the [square brackets]. the first field in the group is 0, second is 1, third is 2, etc. */ ?>