Layering works when each piece has its own space. Get the lengths, weights and focal point right and a stack looks intentional instead of crowded.
Vary the lengths
Leave about two inches between chains so they sit in separate rows. A common three-piece stack is 18, 20 and 24 inches. The shortest chain frames the collar, the longest carries the pendant.
Mix the weights
Pair one heavier chain with one or two finer ones. Two chains of the same width compete with each other; a clear difference in width lets both read.
Choose one focal point
One pendant should lead. If you wear a large custom piece, keep the other chains plain. If you prefer two pendants, put the smaller one on the shorter chain so they do not overlap.
Keep the metal tone consistent
Matching tones is the safest approach. If you mix, repeat each tone at least twice, for example a two-tone watch with one white and one yellow chain, so the mix looks deliberate.
Looking after a stack
Take chains off one at a time, fasten each clasp, and store them separately so they do not tangle or scratch each other.
