As you work on things or change things you will frequently have to disconnect a lot of cables. It can be confusing or a pain to remember exactly where everything connects back in.
Get yourself a pot of nail polish, brightly colored and a pack of toothpicks and use the toothpick to put marks where you need them. In fact, whether you are building quads or repairing your Aston Martin, you should ALWAYS have nail polish and toothpicks in any well stocked toolkit; you'll be amazed how handy they are.
For motor cables into your FC, for example, you can use dots to mark channel number (As in the pic below) and this is a lot easier than trying to write the number really small with a marker or such.
For other connections, take the toothpick and run a line from one side of a connection to another so you have a quick visual reference - line up the marks and voila!!
I figured I'd type up the instructions for setting up the FlySky FS-I6/Turnigy TGY-I6 flight mode switches for the ardupilot manual.
l'll include a link to the video at the end as well.
You will use a 3 position switch (SWC) and a 2 position switch (in this case, SWD. You can use any of the 2 position switches, but it makes sense to use the one next to SWC for ease of reach). This will give you 3 SWC positions with SWD in it's first position and 3 SWC positions with SWD in it's second position, giving you a total of 6 positions for your 6 basic flight modes.
Click OK to move out of the home screen.
Now click your UP or DOWN button to move to SETUP.
Click OK to enter the SETUP MENU.
Click your DOWN button to move the selection arrow to AUX. CHANNELS.
Click OK to enter AUX. CHANNELS.
The selection arrow should be on CHANNEL 5. If not, click OK to cycle through and select CHANNEL 5.
Click your UP or DOWN button to cycle through the assignment options until CHANNEL 5 shows SWC + D (or SWC + whichever 2 position switch you wish to use).
Click OK to cycle down to CHANNEL 6.
Click your UP or DOWN button to change the assignment option to SWD (Or whichever 2 position switch you selected in the previous step).
Click and hold CANCEL until your TX beeps and returns to the previous screen, to save the settings.
Click your UP button until the selection arrow points at END POINTS and then click OK.
Click OK to cycle down to CHANNEL 5.
The arrow will be pointing at the low END POINT.
Use your UP or DOWN button to adjust this number.
While doing this, have SWC and SWD in their first position and have your mission planner open at INITIAL SETUP/MANDATORY HARDWARE/RADIO CALIBRATION and have your MP connected to your quad via MAVLINK. It may be helpful, before doing this to click on INITIAL SETUP/MANDATORY HARDWARE/FLIGHT MODES and write down the PWM values for each flight mode to save you having to constantly click back to it during the next step.
As you adjust your END POINT, watch the value of CHANNEL 5 on your MISSION PLANNER and adjust it until it falls within the PWM value required for FLIGHT MODE 1.
Repeat this step for SWC in Position 2/SWD in position 1 for FLIGHT MODE 2 and repeat this step for the remaining flight modes.
You will need to adjust and tweak the low and high END POINTS. To move the arrow between the LOW and HIGH END POINT, move SWC to position 2 and move SWD to position 1 for low and position 2 for high, but remember to move your switches back to the correct position for whichever FLIGHT MODE you are setting once you have selected high or low.
Once END POINTS are set, click and hold CANCEL until your tx beeps and returns to the previous screen.
That's it. You should now be able to select all six flight modes using the combination of SWC and SWD.
My values for END POINTS are 88% for low and 71% for high. Yours may be the same or may need different settings. Just keep adjusting until you have the values correct.