IIRC this board has a solder pad at the top left corner of the board. I would connect the antenna (1.25-inch stranded, insulated copper wire) there. In later designs I have replaced the solder pad with a through-hole, which is more robust. Be careful not to move the soldered antenna around too much since you could dislodge the solder pad.
Ah, okay. That's going to take some soldering wizardry to get that on there now as I've soldered it to the bottom of the teensy. Oh well.
Another Q, The esp8266 just seems to be sending back test, test, test, test every 500 milliseconds or so. It doesn't seem to want to take any commands either. Do I have to flash it?