Start by opening the Oculus application on your computer.
Find and select "Library" on the left hand side menu.
This may appear with a blue dot beside it, indicating that there is a new update that needs to be installed.
In your Library tab you will see a list of the previous software updates that have been installed.
If there is a new update that needs to be installed, you will be able to select and initiate this new download here.
*Note: Oculus updates typically download in 12 separate stages. You only need to initiate the download once for all stages to download. However, please make sure the total number of downloads has completed before closing down the Oculus application or your computer.*