Get the PCB from https://oshpark.com/shared_projects/JQpvX13E

You can also take the Fritzing file from the repository, generate Gerber files and order it somewhere else, or even make the PCB yourself.

Apply the solder paste, place the ATtiny85, capacitor and the accelerometer, and heat carefully with a heat gun or a reflow oven.

Solder the servo plugs and the power plug normally.

Attach the horns to the servos using screws and glue, and put them inside the ears according to this diagram:

Program the ATtiny85 using a programming clip and an ISP programmer. The code is at: https://bitbucket.org/thesheep/ears/src and you can either use the Arduino IDE to flash ears.ino, or enter the "main" directory and run "make flash".

Connect the servos and the battery, and tape the PCB at the top of the headband.