Before we can motorin' there's a little soldering to be done. This step will attach the 2x20 socket header so that we can plug this HAT into a Raspberry Pi, and the terminal blocks so you can attach external power and motors.
Start by plugging the 2x20 header into a Raspberry Pi, this will keep the header stable while you solder. Make sure the Pi is powered down!
Heat up your iron and solder in one header connection on the right.
Once it is soldered, put down the solder and reheat the solder point with your iron while straightening the HAT so it isn't leaning down
(For tips on soldering, be sure to check out our Guide to Excellent Soldering).
Check over your work so far, make sure each solder point is shiny, and isn't bridged or dull or cracked
Now grab the 3.5mm-spaced terminal blocks. These will let you quickly connect up your motor and power supply using only a screw driver
You will have 3 x 2-pin terminal blocks and 2 x 3-pin terminal blocks
Slide each of the 3-pin terminal blocks into a 2-pin to create two 5-pin blocks
Slide the terminal blocks along the edge of the HAT, so that the 'mouth' of each block is facing out.
You can use scotch or other plain tape to keep the terminal blocks flat against the PCB while you solder