All cosmetics and displays and should be kept in a cool, dry place that is not directly in a lighted area, especially if a natural line of cosmetics is being used; too much heat and moisture will adversely affect the makeup due to the fact that it does not contain preservatives. A lack of preservatives will cause cosmetic products to go rancid and may change the color of cream-based products.
Be sure that every time a product is used, it is properly cleaned. Furthermore, do not dip brushes into jars; use a spatula instead. When working on oily or acneic skin, be especially careful because the sebum can get into the powder with an applicator and shorten its shelf life.
Bacteria, mold, and fungi that grow in cosmetics may cause various, unpleasant skin reactions. Because they thrive in warm and humid conditions, cosmetics should be stored in a cool, dry place away from direct sunlight. It is not recommended to store makeup in the bathroom because it is a room that is very damp. Cosmetics do not like heat; it causes them to deteriorate quickly.
Clients can store cosmetics at home in the refrigerator (especially creams and lotions). The ideal temperature for these products is between eight to 12 degrees Celsius or 46.4 to 53.6 degrees Fahrenheit. Moisturizers feel cool and wonderful on the skin when kept in this fashion.
Mascara should be replaced every three months, unless using an all-natural formula as they may dry up more quickly. If a client is prone to eye diseases, choose a waterproof mascara; caution should be used with this product because it is harsh on the eyes and eyelashes when used daily. Vaseline-based solvents make an unfavorable environment for bacteria. In order to maximize mascara’s shelf life, try to minimize the time that the tube is open and do not leave it open when it is not in use.

Thoroughly cover jars, tubes, and bottles and avoid prolonged contact of cosmetic products with the air.
Try to avoid using the same foundation for more than one year. When using a foundation, carefully close the box and never come into contact with the cream straight from the jar; it is best to use an applicator instead.
Eyeliner can last for extended periods of time, especially if they are sharpened on a regular basis and the cap is always replaced after use.
The key to properly storing cosmetics is to avoid bacteria growth and keep everything sanitary. Keep in mind that when using a good mineral makeup line, bacteria does not grow well in the alkaline environment found in pure minerals, so there are naturally fewer irritants to exacerbate sensitive skin. They are more beneficial for all skin types because they contain physical sunscreens, as opposed to chemical sunscreens, to protect the skin.