Thread a single bead onto your string or wire and secure it by tying one end or using a crimp bead. Note that you can get something known as an eye pin at your local craft store. These eye pins have a flat end, allowing you to thread beads onto the pin without them falling off. Use whatever works best for you. If you want your decorations to have a little give, use string. If not, some wire or an eye pin will do.
Add more beads onto your wire or string to create a pattern. Try making more than one decoration for your Shepherd's hook and have them dangle at different lengths for an artistic effect. Use a theme if you plan to give your bookmark as a gift. For example, if this gift will be for a baby shower, find beads that look like baby blocks, teddy bears, bottles and rattles.
Avoid covering your entire string or wire with beads as you'll need to use some of it to attach your decorations to the eye of your Shepherd's hook. Loop the free end of your string or wire into the eye of the hook and either tie it off if you're using string, or twist the wire around itself three times.
Use pliers to close off the wire if it's too hard to twist with your bare hands.
Cut off the excess wire or string by using a pair of scissors or jeweler's grade wire cutters. Sand the end of your wire with a metal file to remove any sharp edges.