Basically, you first must choose whether you want to do "healthier" necklaces/bracelets, or candy?
For the "candy jewelry":
Do you want to get "fancy", by using fondant to mold pendants into fancy shapes or designs, or do you just want to string gumballs, jelly beans, etc.? Flowers can be made from "Tootsie Rolls", mini-marshmallows, gum drops, etc., and for this type of necklace or bracelet, I would use string, twine, ribbon, or even jewelry wire, (depending on whether or not this is for kids or adults, and whether or not you are actually going to eat it!), a needle or plastic yarn needle. Stringing on "shoe string" licorice could be tricky! This would make it fully edible, but you can't knot the licorice, as it just tears or breaks. You can braid licorice though! Yes, I pulled apart some "Twizzlers" licorice, and braided it like a friendship bracelet! (Check out the pic above within the slides!) That was fun, and takes a bit more time, so this would be a more suitable project for kids 9 and up. (Also, you can't knot the ends, so I had to kind of wrap and press the ends together.) Note: make sure to use "fresh" pull-apart licorice for the braiding, as it's more sticky and easier to braid on a clean surface.
There are also so many fun, and colorfully- shaped candies, that would also be great to use as well! (For example, jelly bean "rocks". They really look like rocks or pebbles, and are perfect for resembling "stone" jewelry!) If you have no plans of eating this jewelry, it's a great way to use up some of that holiday candy that's sitting around!
For candies that don't have holes already, you may have to use jewelry wire, a needle and embroidery floss, or use a skewer or an object to pierce a hole through the candy. I recommend that you not use hard candies for stringing- only candies soft enough to pierce easily for safety reasons! Also, if using taffy, tootsie rolls, etc. for flowers or stringing, be sure to place the jewelry on plastic, or a non-stick surface and in a cool dry area, as the candy is very tacky, and can easily melt and stick to things!!
For the "snack jewelry":
Use kitchen twine, or string, and find food items that already have holes in them to make it easy even for preschool aged children to do! Cheerios, fruit loops, pretzels, etc. works really well. And if you want to string on some popcorn, yogurt covered raisins,dried fruits, etc., use a large plastic yarn needle, (you can find these at craft stores in sets of 4), for those items that don't have holes, but are soft enough for a plastic needle to go through. This activity is perfect for classrooms, (this could also be a math, color, or texture lesson for younger children), outdoor camping or hiking craft- great as an energy source for long trails or biking, and doesn't take up much space! And also makes for a fun party or holiday activity- you can totally find snacks to work with any theme!
Whether you wear it, eat it, or both, make the effort to do this fun project sometime!