Hi, btw this is Elizabeth. I've set this account up to use while I'm in Sweden, but was just having a potter around.

Anyway, knots for sewing: I'm with Helen on using double thread, but I don't bother with a knot at the end. Instead you sew several small stitches on top of each other (careful with the first two that you don't pull the thread all the way through - after that it will hold). This has the advantages of being quicker, stronger, and not leaving a lump in the fabric above the big knot. Horay! And you can use the same method to finish off.

Have fun with your sewing maching!