Form Hints is text that inside the field that disappears when the visitor begins typing in the field.
Form Instructions are little tooltips that pop up when the visitor hovers over the field.
1. Go to Marketing Activities.
2. Select your form and click Edit Form.
3. Select your field and enter Instructions.
4. Click Finish.
5. Click Approve and Close.
Don't forget to approve the landing page draft created by the form changes.
There's so much that you can do with forms.