Step by step instructions on upgrading Farms 133 pack?

Greetings.

Are there any step-by-step instructions available for updating the Farms 133 theme pack?

My "WPMU DEV Theme Updates" displays a "download upgrade".

I click on this and I'm taken to:

https://premium.wpmudev.org/project/farms-133-theme-pack/

I've downloaded the zip file.

But not sure what to do next?

Do I simply unzip this and overwrite the current themes collection using FTP?

Can I upgrade the current themes from within my Dashboard?

Thanks for any guidance on this.

Best Wishes,

PRODOS
Melbourne, Australia