Step 3: Schematics
Now to calculate the value of the 24 resistors you can use this site :
You should first get some specs on your LEDs, you should know their forward voltage and forward current, you can get this info from the seller. The circuit operates on 5V so your Source voltage is 5V.
Download the original file to see the schematics better.(press the "i" icon in the top left corner of the picture)
I have added a PCB layout of the control board, and i want to thanks Willard2.0 who made this layout and let me use it so thanks a lot mate!