You can only leave remarks such as "Just Listed" or "Coming Soon" for listings if they are your own ones. So this article doesn't concern the MLS® listings. 

If you have an open house date entered, that of course is the most important note concerning this listing. So other notes like "Just Listed" won't be shown as a banner any more. Instead the banner will look like this:

How to enter an Open House Date:

Entering such an "Open House" note for a listing is very easy. Just go to "Listings" under the menu tab "Manage Listings".

Now "edit" the listing.

Under "Basic Info" you can enter the date for the upcoming Home Tour.