Used to have 2 sergers so when I needed to do a simple 3-thread serge I'd go to that machine as its so difficult to thread or at least it was for me. Reason why I got the 2nd serger, a Babylock air threader. Got rid of the 1st serger last year as I just wasn't using it much so why keep it? Anyway, I just tie whatever color thread I need to change to, pull it thru except for the needle and it makes it so much easier for me now. I do the same on my quilting machine, just tie the new thread to the end and pull it thru till it reaches the needle.