Hold the spool of thread vertical then turn it upside down. Look to see how much of a twist or curl has on the thread when it is about 8 inches off the spool. Now do it the opposite way and see how much of a twist the thread has. Place the thread back on the machine in the direction which had the least twist. This will be the way it was wound on the spool at the factory. Some machines are finicky and need to be done like this. Try adusting your upper and lower tension to get them in balance. Change your needle and hold your thread when starting to sew. Also, a little longer stitch length might help. Good luck.