Author’s notes
Sometimes you may want to add a comment or note to a node. This can help to better understand your application (both for yourself and others), and can also be used while developing. Think of changes, todo’s and general points needing attention.
You can add these kinds of notes in two ways: with ‘yellow notes’ and with comments.
Yellow Notes
In order to add a yellow note, double-click the node to which you want to attach the note. Press ‘more’ on the bottom. The name of the button will change to ‘less’. Fill in whatever you want to say and press [OK].

In the graph menu the node will get a red ribbon, so you or others can see there is a note for that node.

Comments
If you want to add a comment, you can do so in two ways.
The easiest is by selecting [DATA > Comment]
.
A screen will appear in which you can add your comment.
You can also add multiple comments to a node.

The second way is relevant if you use the source code of a model. You can do this by placing your text in between { and }. For example, your source may look like this:
interface address;
interface name;
{The user needs to enter his name and address here}