Working with annotations
Most of the annotations and markup tools are intuitive and easy to use. Simply drag them into the desired spot, and then resize as required. If necessary, you might change the properties to add some text or adjust the transparency.
There are a few that require a bit of explanation, however, and this section deals with them.
About the annotations’ right-click menu
The annotations are supplied with a right-click menu, some of whose options – like Properties – allow you to modify the markup and add or change associated text.
Others, however, are not operational. Mark with Checkmark and all of the options under Review have no effect on the annotations you make in the PDF review file.
One option however – Flatten – will merge the markup symbol into the review file so that it can’t be removed. It's a way of a producing a read-only annotation. Unfortunately, it also removes your review comments from the Annotations view (or from the Comments Pane, if you're using the Web Reviewer) so it's up to you whether it's worth the trade-off.