I only knot occasionally. So, I’ve developed a way to knot using either a corsage pin or an old stick pin that I have. (A straight pin is not strong enough for this.) However, if you plan to do a lot of knotting, you might want to consider either learning to use an awl and a pair of tweezers, or for a more high tech approach, take a look at a tool called the tri-cord knotter. These tools will make it easier for you to make consistent and tight knots. Most bead vendors sell tools which are specially made for knotting. Many of them also offer books and even videos on this technique as well.
For my way of traditional knotting, along with the corsage or stick pin you just need your beads and choice of cord. For this demonstration, I’m using burgundy colored nylon no. 4 cord and 6mm mother of pearl beads. I’ve chosen to use contrasting colors so they show up better in the pictures. Of course, if I were to make a necklace, I’d match up my cord to the color of my beads.