@safia2 I used an arms legth for all the strings but the white I did the loop with. I fold them in half, If you wanted it to be longer, I would do an arms and a half and a little less than two arm legths for the loop color.
@safia2 you can also calculate the string length because not all strings are used equally. I've written a tutorial about that.
And if you do run out of string, you can always attach new string. Alex's Innovations has a video on replacing broken string that explains a few methods.
