First of all, common nail polish contains a lot of volatile solvents, which is why nail polish is very easy to dry, because the common nail polish contains acetone, ethyl acetate (commonly known as banana water) and other components are very volatile, they ran into the air, the bottle is only solid, so dry.
Since this is so, that adds these dissolvent composition, can solve a problem, but acetone, acetic acid ethyl ester (commonly known as banana water) belong to inflammable and dangerous chemical, also have commonly only chemical reagent shop just have sell, also do not have small package, compare trouble so. Nail polish thinner can also be found on the market, but it takes a lot of thought to find it.
The problem is much easier with natural water-based nail polish. When applied to nail polish, the bottle is left unsealed and the water evaporates into the air, especially in summer. So after you use natural nail polish two or three times, if you notice it thickens, you can drop a drop of water in it, shake it well, and your nail polish won't dry until you're done :)
Special note: adding water to prevent the polish from drying out is not suitable for normal nail polish (normal nail polish is oily, while natural nail polish is water-based).
You can also drop some nail polish remover and shake it. Put the nail polish you bought next time in a dark place and screw down the bottle cap. It's a good idea to keep it in the fridge for a year or two. A good idea from a friend is to add a few drops of perfume to your already dry nail polish. Be careful not to dribble too much. Still have, belong to metallic burnish kind not appropriate. Will make it lose its original luster. What kind of perfume all right, don't too bad line...
Make sure you screw it up when you use it again, and keep it out of the light for a while so it lasts longer. If the nail polish is dry, you can also drop a small amount of nail polish remover, and then stir it to use again... But it will thicken quickly and lose a little of its polish. It's best to buy a special thinner.
Use special armour oil diluent, drop 3 drops or so on one time, shake even, after placing half a day, let the air among them platoon comes out, when besmear armour oil won't have bubble.
Remember to clean the bottle mouth and brush with nail polish remover or thinner, otherwise the bottle sealing is not good, nail polish drying faster.