If the salt in your salt cellar gets too moist it sets in a clump. Put some grains of rice in with the salt to absorb moisture.
If the salt has set too solidly for the rice trick to work, remove the cap from your salt cellar and scrape out the salt onto a baking tray lined with kitchen foil. Place it in a warm oven for 5 minutes to dry it out. Meanwhile, wash out the salt cellar and dry it thoroughly. Then pour the salt back into it, with a few grains of rice.
