Since TF2 on Steam fully supported on Linux, I hardly switched my dual-boot machine to Windows OS. So most of my writing here mostly will be Linux specific. However feel free to ask me through comment if you want me to help you up to Google specific guide for your platform.
For now, I'm on Archlinux. However, I'd like to try out another distro so I'd like to write up my Debian Xubuntu addition (actually replacing my Arch) to my existing dual-boot Win+Arch system.