The right panel you refer to is probably the split screen page preview stuff handeled by the SilverStripeNavigator
. I've played around with that a few years ago, but found it was to tightly coupled to the CMS/SiteTree to be of any use for custom stuff.
But here a few other ideas of what you can do:
- add extra infos to FormFields with
->setDescription("hello world")
or/and ->seRightTitle("hello world")
, eg:
$fields->addFieldToTab('Root.Main', [
(new TextField('MyFieldName', $this->fieldLabel('MyFieldName')))
->setDescription('Some help text here')
]);
- You can improve the usability of the admin by grouping in Tabs and adding headlines
$fields->addFieldToTab('Root.SomeTab', [
//...
new HeaderField('MyHeader', 'Personal Details of this account'),
new TextField('FirstName', $this->fieldLabel('FirstName')),
//...
]);
- Add Help Elements inline with
LiteralField
$fields->addFieldToTab('Root.SomeTab', [
//...
new TextField('FirstName', $this->fieldLabel('FirstName')),
new LiteralField('MyLiteralField', '<p class="message info">A help description here with any HTML you want. Styled what ever way you want</p>');
//...
]);
- build your own custom sidebar.
The Blog Module has a custom sidebar for the "Post Options". You could copy what they've done and instead of putting extra FormFields in there, you could use LiteralField
to add any HTML in there you want to display your help information.

I don't have a code example for that at hand, but I'll imagine if you look at the source code of the blog, it won't be to difficult to figure out how they built the sidebar: https://github.com/silverstripe/silverstripe-blog