Here's the long and short of it

The most important factor in layering is length. Generally speaking, you need a visible spacing between strands of around an inch or two. It could take some trial and error to find the right combination of lengths; for example, try wearing a princess-length necklace with a matinee-length necklace or a choker with a princess-length piece. Try with a few different arrangements until you get the mood you want. You could want them staggered widely for a dramatic impact, or you might like them piled closer together. Just make sure they aren't all exactly the same length, otherwise you'll have a jumbled mess.

Select the Proper Amount of Strands

You are not required to stop at two necklaces; you are free to add another three, four, or even more. Although there is no set rule in this regard, try to avoid going overboard. While two pieces can be elegant and go with most outfits, three to four can make your necklaces the highlight of your look. This is another instance when experimenting with various pairings to find which best matches your style is appropriate.When in doubt, take Coco Chanel's suggestion and take one item off before leaving the house after taking a glance in the mirror. 

Avoid Getting Tangled Up

Avoiding allowing your Swarajshop necklaces become tangled when you're wearing them (or not) is one of the toughest aspects of this trend. The use of chains of various lengths will undoubtedly aid in tangling prevention, but if you're still concerned about a knot or two, there are other choices available. Here's a tip you might find useful: Clip the clasp from one Bridal necklace onto the end of the second necklace that is opposite it, then do the same with the other clasp. or a tutorial, view the video below:

A professional untangling service is always an option if you've previously tried this and your necklaces are still all twisted (really a lifesaver for those insurmountable knots).

Work to a focal point's side

Start with a focal point and build around it to achieve a layered design that isn't overly heavy or congested. Starting with a medallion or charm and adding a shorter, thinner chain made of the same metal is a basic method to sport this look. To avoid going crazy by attempting to wear everything you possess at once, start with one statement item and match lesser or longer chains to compliment the primary emphasised design.