Start off with soldering the surface-mount components first (recommend using .020" diameter solder.) Solder the 10K ohm resistor on R1, the 220 ohm resistor on R2, and the .1 uF capacitor on C1.

Of course, solder the rest of the components to the board.

For cleaning, use 91% (or higher) isopropyl alcohol and a toothbrush (or some other clean non-metallic brush.)

Check for any short circuits after the board is dry.

Instructions for configuring your Attiny85 if you put in a fresh Attiny85 on the board:

I would recommend setting the internal oscillator to run at 8 MHz. The board was designed on the premise that the internal oscillator would be used to free-up 2 pins for GPIO usage.

First make sure your USBasp (or other programmer you're using) can talk with the Attiny85. For the USBasp try this:

avrdude -c usbasp -p t85 -v

If you did what I did, and updated your USBasp to the latest firmwave, you will get something along the lines of target did not respond. What this error means for us is that our USBasp's programming clock speed is running too fast for our new Attiny85, which comes from the factory running only at 1 MHz. To fix that we need to use the -B option to slow down the programming clock speed such as -B 4. So the command to try is:

avrdude -c usbasp -p t85 -v -B 4

You should get a response that shows the current fuses.

Now for setting our attiny85 clock to run at 8 MHz:

avrdude -c usbasp -p t85 -B 4 -U lfuse:w:0xe2:m -U hfuse:w:0xdf:m -U efuse:w:0xff:m

And there you go, since it's now running at 8 MHz, you no longer need to use the -B option when uploading firmware.

Configuring the Arduino IDE:

http://highlowtech.org/?p=1695