Aim to clean your chandelier with either the “crystals on” or “crystals off” method every year for a fixture that remains shining and bright.  Observe your chandelier periodically for visible dust, cloudy crystals, or spots. These are all indications that you should clean your fixture right away. Clean more often if your chandelier is located in a kitchen, as it will build up more grease and grime than in other areas of the house. Entryways are another area in which a chandelier may need more frequent cleaning. If you’ve never cleaned your chandelier, opt for a deep clean by performing the “crystals off” method. Otherwise, the less time-intensive “crystals on” method will typically suffice for regular cleaning. Choose a deeper clean particularly if there are stubborn spots or a cloudy, milky quality to the crystal that isn’t removed by a simple dusting. To make your clean last longer, use a soft feather or lambswool duster to lightly clear dust from the frame and crystals. You'll need a stepladder, but you do not need to disassemble the fixture.  A good general rule is to dust every few months, or whenever you notice a visible layer of dust or haziness on the crystals, frame, or bulbs. It’s also a good idea to dust before any wet cleaning, as you can remove larger dust and dirt particles ahead of time.
Try to clean every 12 months. Decide on a deep or shallow clean. Dust in between cleanings.