The size of the thread will depend on the size of the drill hole. I would steer away from the larger sized thread as it may be a tad too thick making the knots too large. I would start with the middle size. I think Pattye still offers a beginners stringing kit with everything you will need! She even sells orbit clasps, which I know many of the ladies here prefer. Oh, and I love the large eye needles she sells, they work with any size drill hole and thread. ETA: as far as thread colors go, you can really get creative with white pearls! If you like a pop of color on a strand, or one that picks up overtones she has some lovely pastels. You can also go bold with a red or blue, or subtle with an ivory or cream.