1.   How often should I shampoo?

There's no harm in washing your hair every day, unless you start to see a lot of breakage. The entire wetting, drying, and styling process takes moisture out of your hair, so here's a rule of thumb:

Wash every day if you have oily hair, live in a polluted city or humid environment,or work out daily.

Wash every other day if your hair is normal or combination (with dry ends and oily roots).

Wash every few days if your hair is on the dry side (this includes curly or color-treated hair) or if you live in a rural environment or dry climate.

2. Is it possible to use too much shampoo?

As long as you rinse it all out, you really can't use too much.

 A dollop the size of a quarter is usually enough, but hair length is also a factor. 

Lather can be drying, but since it only sits in your hair a few minutes, it's safe for all hair types. 

3.  What is the ideal water temperature?

Warm water will work up a nice lather and help dissolve the soap so that your hair rinses clean.Avoid really hot water, which can actually make your hair limp.For the final rinse, cold water is best —— it will lock helpful ingredients into each strand and make hair look shinier.

4. It takes me a long time to use up a bottle of shampoo —— does it expire?

Most shampoos have a shelf life of two to three years.A product that's older won't harm your hair, but it won't be as effective, It’s signs are separation and/or a change in color or smell. 

5.How often should I use a deep-cleansing or clarifying shampoo?

If you use a lot of styling products, live in an area with mineral-rich water, or swim a lot, you should deep-cleanse or clarify twice a month.Oily types: It's a good idea to use a daily clarifying shampoo every time you wash. For the rest of us: Use a clarifying, purifying, or chelating formula (which removes mineral residue) if your hair looks dull or has become resistant to your regular products. If you color your hair and worry about the effects of deep cleansers, one that's safe: vinegar. Mix one-quarter cup white vinegar with one cup of water. Leave it on your hair for one to two minutes after shampooing and conditioning, then rinse out. 

6. Are costly salon shampoos better than drugstore kinds?

Shampoo is not one of those "you get what you pay for" products. How much you like a formula depends on your personal preferences (in terms of scent and texture) and how it works on your particular hair. A $5 shampoo may smell good to you and leave your hair looking terrific, while someone else may feel the same way about a $25 bottle. That said, there are a few facts to know: The big companies that create drugstore brands put a lot of money into research and new technology, but they can still keep prices low because they manufacture their products in mass quantities. Expensive shampoos have advantages of their own: In general, they're gentler and contain a higher concentration of high-quality ingredients (e.g., a conditioner that penetrates deeper into each strand).

7. When is it time to switch shampoos?

Sometimes the same bottle that's always made your hair bouncy and shiny can leave it lackluster without warning. "It's a popular perception that shampoo suddenly stops working, but it's not the shampoo that's changed.Unless a product's label alerts you to a "new"or "improved" formula, it's the surface of your hair that's different. But this doesn't necessarily mean you can't go back to your old favorite. If buildup is causing the problem, first clarify, then bring back your beloved bottle. No improvement? It may be time to switch for good. A simple self-test: Look at your nails. If they are ridged, peeling, or seem to break more easily, you're experiencing the most common of all changes — aging,which leads to water loss in our cells and tissues. So while you're still using your trusty oily-hair formula, your hair may be drier than it's ever been. Buy a moisturizing version, or ask your stylist to diagnose your hair's new needs.  

8. Do I really need conditioner?

Conditioner is essential. It finishes what shampoo starts, in terms of making hair manageable and repairing problems like split ends. "Everyone's hair is damaged You may go through many conditioners before you find the right one, but you'll know when you've met your match."When your hair is properly conditioned, it holds a style better.