You can create notes in your client's profile to add important information. If the note is higher priority, you can Pin it so that it will display at the top of the Activity Feed.
Go to the Contact Profile and select Actions tab and then Notes tab. Click the Pin this note check box.
After you type in the information, click the Save Notes button.
To view the notes go to Activity tab, Pinned Notes are displayed at the top and regular Notes according to the date it was created.
There is an option to Pin Notes or Un-Pin it, so it is easier to find each note in the client's Activity Feed.
If you already created a note and you want to keep it on top of your client's Activity Feed you just need to look for it and Pin it, once you don't want it anymore you can Un-Pin it anytime.