Hello Lillian,
When you lift the presser foot up and down can you see the tension discs moving ? if you can then you just need to adjust the tension, if the discs do not move then something is causing them to stick in the open position, assume they move when you move the presser foot up and down, make sure when you thread the machine that the presser foot is in the up position so the thread goes completely through the discs,make sure there is no thread stuck between the discs causing them to stay slightly open, you should have your tension set about number 5 or 6, give it a try and see how it sews, if this does not cure the problem you may have to undo the tension itself but I will guide you through, you will not have to take the tension completely apart so don't worry, e-mail if you have a problem.
Ken
drivewithken@blueyonder.co.uk
August 2007