The servo listed in this tutorial is good, the salvaged resistors i was using weren't.
It doesn't have to be pretty or fancy, this one is kinda spread out to look pretty and show individual parts. My wiring is a bench test of unsecured spaghetti because it doesn't matter for this pic. Just look at the board, It's the same as the single led in the first post. I like to color code (like shown) but it doesn't matter if you don't.
I've got the 2 resistors in the V shape replacing the potientiometer, their other ends go to the outer leg pads. I used 2.2k ohms here. That's 2,200 ohms. Exact value on these isn't as important as having them the same value. This makes the servo think it's centered, so it could be used on a 3 pos switched channel to run 2 circuits at different times. If you use a light that's not an led, you'd have to use a Diode to turn it off at the wrong polarity since they don't care about polarity, they work either way.
The 3 resistors hanging off the side of the board are current limiters for each color in my circuits. Resistor sits on the old motor hookup pad, the other wire comisg back off the circuit ties to the other motor pad.
My example is a servo board running 2 headlight, 2 yellow markers, 2 red markers, and 6 taillights. These are basically run as 3 parallel circuits, one for each color, and they all tie in at the motor pads on servo board.
To run Red leds, you're usually going to want around 470 ohms.
To run Yellow or Green leds, you're usually going to want around 220 ohms.
To run White or Blue or Purple, you're wanting something more like 110 ohm.
These values aren't exact. Or anywhere close to optimized for your leds. This is just an easy way to get lights without caring about forward voltage, current drop, and any math. There is no tracking down datasheets for parts you don't have a build company or part numbers for.
Yellow takes more power than red, if you matched their resistors only red would light.
White takes more power than yellow.
Blue, white, and purple are all filtered blue
Green is filtered yellow.
If you use a higher value resistor, light get's dimmer.
If you put a lower value resistor on, light gets brighter.
If you put a much lower value resistor on, light goes flash and never works again.
If you want the light to turn on/off slower more like a halogen or incandescent light, you can put a CAPACITOR across the motor pads where your lights attach. Also if your lights are kinda strobing, a cap can help smooth out the pulse width modulation. Don't use an eletrolitic cap that's polarity sensitive, just use the cheap ceramic disc caps like we used on motors.
How do you eat an elephant? One bite at a time.
Complex circuits can get overwhelming, so just think about 1 wire or led at a time.
Go put some lights on something, it's not that tough. Show us your lighted stuff.