I am looking to make a necklace where the beads are on the thread but not connected to other beads or spacers. Do I just need to knot around the bead or do I need to do something different to hold it in place?
When using Invizi™-Cord or other types of invisible cord, knotting and/or gluing beads in place are better options as crimp beads can damage the cord; this is called Illusion style stringing. Another option is to string the bead then pass the thread through the hole in the same direction to secure it in place. This technique allows for repositioning of beads, if needed, later in the design. E6000® Jewelry and Craft Adhesive is a great glue to use when working with invisible cord. It is a strong holding, clear glue that remains flexible after curing.
When using Accu-Flex® beading wire, crimping and/or gluing work well. A cyanoacrylate adhesive, or super glue, is the best choice for this type of design as they are quick drying and suitable for using with a variety of surfaces. Loctite® 409 gel might be the best choice overall as it has gap filling properties as well as will not drip.
Still another option is Bead Huggers™. These are used in place of knots to separate lightweight beads as they stay snug against beading wire and act as a buffer or placeholder to keep beads in the position you want; this is called the intermittent stringing technique.