I used to use a leader or "spider," as someone called it, but found that if I simply hold the thread tails snugly behind the machine, I never have to mess with another piece of fabric and snipping it off. If I had a scrap quilt planned, I might go back to the leaders and enders, however. But even starting a leader on a diagonal would mean holding those thread tails at the start. Each machine sews a little differently. I could get away with just beginning at the fabric edge with my old Kenmore.