Soldering the components
Step 1 – The Brain board
Let’s begin with the Brain board. 
Take 2 sticks of pin headers and cut them to size so that you can solder them onto the Brain board’s PCB.
You need to trim them with your diagonal cutter pliers.
In the end, you need to have one 22-pin header and one 11-pin machined header. 
The pin headers need to be soldered so that they’re vertical to the board.
You'll notice that one row of pins is shorter than the other. Make sure that that you're soldering the row with the shorter pins to the board.
Luckily there is a nice technique for doing just that
1) Solder just the first pin of one row of headers 
2) Check that the pin header is perpendicular.
3) If the header is slightly skewed and needs adjusting, melt the solder and tilt the headers with your fingers. (Watch out not to burn yourself.)
4) Check if the headers are aligned correctly, if not then repeat the process 
If the header is vertical to the board, you can solder the rest of the pins. 
If the header is vertical to the board, you can solder the rest of the pins.
Solder the second row of the headers as well.
Make sure that they’re vertical to the Brain board!
The results should look like the photo on the left. 
Step 2 – Attaching the Brain board onto the Main board
Step 3 – Soldering the Brain board to the Main board
Step 2 – Attaching the Brain board onto the Main board 
For this, you will need:
1 x M3x10mm black nylon bolt
1 x M3x5mm brass (golden) spacer (WATCH OUT – there are two similar types of brass spacers in your kit and you need the bigger brass spacer here!)
1 x M3 black nylon nut
Put the bolt through the Brain board so it faces out in the direction of the pins.
Then screw the brass spacer on top of it.
Use a small screwdriver for this!
Your Brain board should look like this now.
Then, you can place the entire Brain board onto the Main board where it says “the Brain board”.
Put the plastic nut onto the bolt on the back side of the Main board.
Now that they’re fixed together, we can solder the Brain board onto the Main board.
Step 3 – Soldering the Brain board to the Main board 
Remember the headers you had to cut and solder to the Brain board?
We’re not done with them yet! You need to solder them to the Main board too.
We need to do this in order to establish an electrical connection between the Brain board and the Main board. 
But with a steady hand and some patience, this shouldn’t be a problem for you. Step 4 – The Display board Next, we have the Display board... 
Again, you’ll have to cut the header pins to the appropriate size so that they can fit the pins on the Display board.
You need an 8-pin header row for this.
With the same technique used when soldering the Brain board’s pin headers, soldering this shouldn’t be a problem.
Again, be careful in how you insert the header pins since the top and bottom parts are slightly different. The part you want to insert into the screen is the shorter side! 
Step 5 – Mounting the Display board onto the Main board
For this, you’ll need:
3 x M3x10mm black nylon bolt
3x M3x5mm brass (golden) spacer (WATCH OUT – there are two similar types of brass spacers in your kit and you need the bigger brass spacer here!)
3x M3 black nylon nut
Put the bolts through the holes so that they face the same direction as the pins.
Then, put the spacers on top of them and screw them on. 
Place the Display board on the Main board where it says “LCD display”. 
Place the Display board on the Main board where it says “LCD display”.
Then tighten the three nuts from the back side of the Main board.
NOTE : You can’t tighten the nuts with a screwdriver from underneath, only from above!
Step 6 – Soldering the Display board
Now let’s go ahead and solder the Display board pins onto the Main board.
Through these pins, the Brain board will be able to push all the images to the Display board, so it’s important to solder them properly.
Step 7 – The Sound board
With the Sound board we’re going to have to do a bit more soldering than with the other boards.
For this step, you’ll need:
1 x pin header row
1 x microphone
1 x headphone jack 
First, solder the microphone to the Sound board.
Be careful not to solder it onto the opposite side.
(Check the picture below.) 
2x M2.5 white nylon bolt2x M2.5 white nylon nut
After that, solder the headphone jack, too. 
As before, you need to trim the pin headers to the right size using your diagonal cutter pliers.
You’ll need a 9-pin header for the Sound board.
Again, make sure that the pins you are soldering into the board are the shorter ones. 
Solder them vertically to the board just like you’ve done with the Brain board and Display board before. 
Put the screw through the board as we did with the other boards, then screw down the spacer. 
Place the Sound board onto the Main board where it says “Sound board”. 
Solder them vertically to the board just like you’ve done with the Brain board and Display board before.
Step 8 – Attaching the Sound board
For this step, you’ll need the following components:
1 x M3x10mm black nylon bolt
1 x M3x5mm brass (golden) spacer (WATCH OUT – there are two similar types of brass spacers in your kit and you need the bigger brass spacer here!)
1 x M3 black nylon nut
Place the Sound board onto the Main board where it says “Sound board”.
Fasten the nut from the back side.
Step 9 – Soldering the Sound board
The Sound board shouldn’t pose any problems since it doesn’t have that many pins that need to be soldered.
Plus, by now you should be getting a grip on how soldering works if you didn’t already have the experience.
Solder the pins to the Main board and we’re done with that.
Step 10 – A lot of buttons…
All of these buttons may seem overwhelming, but trust us, after you solder a couple of them, the rest will be a breeze!
The smaller buttons are placed where the numerical keypad is, and just below the display.
The bigger buttons are placed where it says A and B.
Let’s start with the big yellow ones.
Push them into the Main board so that they sit firmly on the board.
Before soldering the push buttons, make sure that they’re perpendicular (vertical) to the board.
This is very important as you’ll have trouble putting the protective casing on the device if the buttons are tilted!
The soldering pads are quite big for these buttons, so you’ll need to hold your iron on them a bit longer.
Soldering the smaller pushbuttons is mostly the same as soldering the big yellow ones.
Please make sure that the pushbuttons are sitting firmly on the board and that they’re not tilted before soldering them.
As we said in the previous paragraph, you won’t be able to mount the casing if the buttons are tilted!
Make sure you solder each and every pin correctly.
Don’t get hasty just because there’s so many of them.
Slow and steady wins the race! 
Step 11 – The joystick
The joystick is still left to be soldered, but after all those pushbuttons, it shouldn’t be an issue.
Once you’re done with that, feel free to turn off your soldering iron and take a breather, because soldering time is over!
Nice job so far, but unfortunately we’re not done yet. There are still a few steps ahead. 
Oh no! It seems we’ve made a mistake during the soldering process!
As you already know, soldering joints must not be bridged as the device won’t work correctly (signals or voltages will get mixed or shorted).
This is a perfect moment to demonstrate how to fix bridged solder joints with a desoldering vacuum pump:
- Push down the plunger button on the desoldering pump
- Place the soldering iron on the bridged joint until it melts
- Place the desoldering pump directly on the melted solder joint
- Press the release button on the desoldering pump, that should suck up the molten solder
- Repeat the process if needed
This will require some practice, but it isn’t impossible to learn! 
Step 12 – The Network board
In order to attach the Network board to the Main board, you’ll need the following components:
The Network board first needs to be inserted into the big connector on the back where it says “Mini PCIE Express”.
The network module needs to be inserted at an angle like this.
Then you need to push it down until it’s horizontal with the Main board.
Keep holding it down and put one bolt through the Network board and the Main board.
Fasten it with a nut from the other side.
Then put the other bolt and fasten the other nut too.
Step 13 – The speaker
Connecting the speaker is easy!
First, you need to insert the speaker’s wire connector through the large hole on the top of the Main board.
Now, place the speaker so it fits snugly between the Display board and the Main board. 
Once you’ve done that, take the white connector with a pair of pliers (or your fingers) and put it in the female connector slot where it says “speaker”.
You should feel a bump when the connector fits in the slot nicely.
Now, place the speaker so it fits snugly between the Display board and the Main board.
That’s about it for the electronics of your Ringo phone, but we’re not done yet!
We still need to place the whole device in a casing and place the button caps.