Thanks for taking the time to learn more about building VR applications in Unity! Bandwidth at the conference site may be limited, so here's the things you should download and install in advance so you can spend you time learning instead of waiting.
Once you've downloaded Unity, make sure to run the installer and include the desktop systems you want to build for and IOS or Android if you want to do mobile VR development. This will take a long time.
From the Unity Asset Store, download these free plugins:
Optionally, download any supporting SDKs for hardware you own and want to develop on:
Optionally, download any additional editing tools you might want to have on hand:
Blender (useful for mesh editing and 3d file conversions) https://www.blender.org/download/
Audacity (useful for audio editing) http://www.audacityteam.org/download/
Krita (useful for image editing) https://krita.org/en/download/krita-desktop/
Some people prefer using a physical mouse to a trackpad to manipulate 3D scenes - if you have an external mouse you may want to bring it along so you have the option.