What is crazing? It is those fine lines that show up on your china, and other porcelain items. Crazing is usually caused from the finish being damaged. To avoid damage to your china, and porcelain, care for it carefully.

Do not put antique china in a dishwasher. The water gets too hot, and the detergent is to strong.

When cleaning antique china line the sink with a cloth or rubber mat. This will help prevent the china from chipping by hitting the sink. If you have a double sink also place a cloth over the center.

Use a mild detergent. Ivory is a good choice. Water shouldn't be too hot, warm is best.

Do not use cleaner with bleach in it. Lemon scented detergent is also a bad choice, it contains acid.

Avoid cleaners with a lot of chemicals in them for china that was made before 1960 or so. Dinnerware made from some point in the 1960's and forward is often dishwasher safe, and can take a little more than the older stuff can.

If you have a piece of china that needs scrubbing use baking soda, it's non abrasive and won't harm the finish.

Avoid extreme temperature changes. Don't store your items where it gets very cold, or very hot. Attics, garages, and other places that have no climate control are not good choices for storing china.

If your china is crazed and has stains there are a couple of tricks to try to remove the stains.
Wear gloves if you try the peroxide treatment, it will burn your skin.
Peroxide.. This is not the peroxide you buy at the drug store. You need to buy the stronger type at a beauty supply store. Mix 1/3 water and 2/3 peroxide. Wet a q-tip, or cotton ball, with the mixture. Dab the spots that need cleaned, this should help to pull the stain out. This is a long process and you'll likely need to repeat it many times to remove larger stains.

You can also try a soak that is a mix of white distilled vinegar and salt. Equal parts of each and soak. I've had limited success with this method.

Storage

It is mentioned above not to store your china in areas where it will meet with extreme temperature changes but I wanted to touch on general storage.

China is meant to be used. Not sit. Likely you have it stored in a china cabinet or a kitchen cabinet. Everyday dishes are going to be stacked, most likely. That's just the way it is.

China, good china, needs a little more protection when storing. Place something soft between plates when stacking. This protects them from scratching one another, and lessens the chance of chips. Hang cups when you can, don't stack more than two high. Depending on the shape of the bowls the two high rule may be good for those as well.
What to put between plates, bowls, saucers?
Plastic is not the best choice, if it gets warm it can pull the finish, or paint. A good choice is paper towels, but a better choice is coffee filters - use a few between each piece.  

Have a suggestion for us to add here? Something tried and true? Let us know, we'll consider adding it.