I installed Platinum virtually when it first came out along with Sonar's installing program.
 
What is the simplest way to install this update?
 
Thanks in advance!

Page 4 of SONAR Membership Release eZine details the packages with updates, they are
The SONAR Artist/Professional/Platinum core
The Anderton Collection and
The Boz Digital Labs ProChannel Collection
 
If you skipped Braintee, you may also want to install the Brian Hardgroove Collection at the top of the Command Center.
 
Run the Command Center and for each package, click the package name and the update button.