Gold is a soft metal, and most of the damage it takes over time isn't from wearing it — it's from how it's stored and cleaned in between.
Take it off before, not after
Perfume, lotion, and hairspray all contain chemicals that dull gold's finish over time, especially on pieces with gemstones or enamel. Putting jewellery on last, after other products have dried, keeps direct contact to a minimum.
Store pieces separately
Gold scratches gold. Tossing multiple pieces into one pouch or box lets them knock against each other every time you move the box. A few separate soft pouches, or a tray with individual compartments, prevents most of the fine scratching that builds up over months of storage.
Clean it, but gently
A soft cloth and mild soap in lukewarm water is enough for routine cleaning — no need for anything abrasive. For pieces with gemstones, avoid soaking; wipe instead, since some stones react badly to prolonged water exposure or certain cleaning chemicals.
Get chains and clasps checked periodically
Clasps are the first thing to wear out on a well-used chain, and a loose clasp is how chains actually get lost. If you wear a piece often, it's worth having the clasp checked every so often rather than only noticing when it's already failed.