Plug in your USB cable. Odin should show a blue/yellow "ID:COM" box.
Used for flashing via an existing recovery or terminal. espresso-common-twrp-3.3.0-2.tar.md5 download
Click the AP (or PDA) button in Odin and select the espresso-common-twrp-3.3.0-2.tar.md5 file. Plug in your USB cable