1. Frequency. How often should I exfoliate?
Our skin has its' own metabolism but exfoliate will help to make sure the top layer goes away and reveal a brighter looking skin. The frequency of exfoliation varies. It depends on skin type, weather, area of the skin... etc.
If you have dry or sensitive skin, try not to exfoliate too much because you need that layer of protection. Therefore, 1 time every two weeks is enough. Only make exceptions for important events such as a big date or a party. If you have oily skin then once every week will do the trick. (Never exfoliate more than once a week.)
Reduce frequency of exfoliation during winter when the skin is more sensitive.
2. Types of exfoliation. Which one should I use?
One common type of exfoliation is a scrub. It usaully has beads or crushed wall nuts as the medium for scrub exfoliation. This is more ideal for rougher oily skin.
Another type is gel. This is more ideal if you're looking for a gentler exfoliation. Good for dry and sensitive skin. (I'm using a gel exfoliation myself.) However, it might not give you the usual exfoliation "texture," but it's still working!!! The gel exfoliation usually has ingredients that help metabolize the skin quickly then make the corneum into little bits then simply wash it away with water. (Dry face before use.)
Last but not least, creme-based exfoliation. It's not that common, at least I don't see them that often, but they're out there. I've never try one before so can't really comment on it. However, I think it will be for the most gentle exfoliation.
3. Area. Where should I exfoliate?
T-zone is definitely the targeted area. Avoid eye area, and if you have dry and sensitive cheeks avoid those areas too. I usually exfoliate my T-zone once a week (once every two weeks during crazy NY winter) and my cheeks around once a month. Find what works for you but remember not to exfoliate more than once a week.
Exfoliation helps reveal a healthier and brighter skin. It is a neccasaty but don't overdo it! Remember to always hydrate and moisturize right after, because skin absorb the best right after axfoliation.