If you bought a Blinkenlight Kit and wonder how to assemble it, here are some short instructions. I suggest you start with the front. The goal is to reach a final result like the picture below.
As tools I usually use a soldering iron, a flux pen, solder and tweezers. The most important part is to not drop any of the pieces to the floor. These small things get lost very easily.
First you should start soldering the resistors. These are the tiny black pieces with the “102” printed on top of them. Apply some flux to the solder pads and place one of them with the tweezers.. Put some solder on the tip of the soldering iron and just touch the pad. Usually the solder just flows into place. Adjust the part if necessary before you solder the second pad. Proceed until you soldered all of the resistors in place.
Next are the LEDs. These are slighty more tricky as these are directional parts. The proper direction is to solder them with the green cathode marks towards the Blinkenlight print. Have a look at the macro shot (click to enlarge) to see this close up. If you can not see the green dots use a magnifying glass. If you solder them in the wrong direction your shield will not work.
Last solder the reset switch. It has no specific direction, just ensure it matches the pads.
The next step is to place the contacts for the back (and solder them from the front). Usually I start with the 3 pin connector and solder it from the front. After this I put in all of the remaining pins. It is always a little bit tricky to ensure that the pins will be in a right angle. Most of the time I just solder one of the pins and then realign as needed. Once I am satisfied I will solder the opposite pin of a row. If everything is still in line I will solder the rest.
If I am lazy I plug the pins into an Arduino and just put the board on top. Then I solder all of them in a row. However if you do not take care you may melt part of the Arduino’s connectors, so I do not recommend this approach. Instead I recommed to “plug” the pins into a piece of soft foam or cardboard. Do whatever you prefer – you have been warned ;)