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A few mornings ago – one of the first clammy mornings of the season – I noticed something hilarious.
Before I put on my makeup, I misted my face with Avene Thermal Spring Water, put on my serum, patted on my moisturised and finished blow-drying my hair - business as usual.
But when I finished with my hair a few minutes later, I unconsciously grabbed my moisturiser again, patted it on, and watched it sink into my skin.
If I'm being honest, I would have done that at least four more times and my skin would still have felt as dry as a sponge; a severe difference from my 'is-this-highlighter-or-is-this-sweat' problem that I usually suffer from in summer months.
You don't have to be Yewande from Love Island to understand the science behind this: a change in weather dries out the skin, so you need more product for the skin to absorb.

But what if my skin isn’t just dry from the weather? Am I just wasting all the additional product I’m applying - or could all that moisture eventually lead to clogged pores and an oil-slicked T-zone?
And what about my serums? my eye cream? my SPF? my body lotion? Heck, what about my shampoo and conditioner?
When it comes to our skin and hair regimes, size actually does matter. Too much of one thing risks wasting product, and too little of another could leave you with serious issues.
With products' varying inconsistencies, textures and thickness across all formulas, it’s impossible to have a one-rule-fits-all mentality.
However, if you want to make sure you’re getting the most out of your product, below are general guidelines that can (and should) be followed, tweaking slightly where necessary.

Moisturiser & Serums
From thick creams to lightweight gels, rules on facial hydration can be a little hazy.
More of something doesn't necessarily mean better hydration. What determines hydration is how a product or ingredient penetrates the skin.
For serum, a 50c-sized pump is recommended. Afterwards, a green-pea-sized serving of moisturiser is usually plenty for the face and neck, especially if it's a clinical brand.
Cleanser
While cleansers come in all shapes, sizes and consistencies the power of your cleanser if far less to do with how much of it you use, and more to do with how often you're using it.
Generally, a 20c sized blob for cleansing is enough to massage around the face and remove makeup with a warm flannel.
However, in the evening, it's always important to double cleanse to thoroughly remove makeup, pollution, sweat and oils. But rather than pumping out one big amount in one go, pump two separate 20c sized blobs.
Eye Cream
If you're going to remember any of the recommended sizes in this article, make it be this one. The skin around your eyes is much thinner and far more delicate than the skin everywhere else on your face.
Using too much eye cream can block pores which result in puffiness otherwise known as under-eye bags. Eye cream the size of a grain of rick is just enough.
SPF
Religiously applying SPF and somehow still burning? This is where the amount of product you use is seriously important. Sun cream should be applied every two hours after the initial application but the amount of sun cream that you're applying could be the difference between sun protection and serious skin damage.
Most SPF bottles will have individual instructions as different formulas require varying application sizes. However, as a general rule of thumb, the face, neck and chest need at least one full teaspoon.
When it comes to your arms and legs, you'll need more of a dessertspoon of suncream.
Hand Cream
Similar to facial moisturiser, more of something doesn't necessarily mean better hydration. What determines hydration is how a product or ingredient penetrates the skin.
Generally speaking, a 50c sized portion is usually plenty for both hands – especially if it's a clinical brand.
Body Wash & Lotions
While you've more surface area to cover, that doesn't necessarily mean you need more product.
For body wash, a 50c sized portion for the arms, another for the legs, back and body. As for body lotion, follow the same 50c rule for hands and arms, but when it comes to the rest of your body - use an amount equal to an ice cube.
Shampoo & Conditioner
Tend to use half a bottle of shampoo in just one wash? Yeah, apparently that's not right either. Most hairdressers recommend using a 10c sized blob of shampoo. You should emulsify the product through your hands before applying it to your hands. If necessary, add water.
As for conditioner, you've been using far too much of that too. The amount of conditioner you use is solely dependent on how much hair you have. However, as a rough guide, start with the same amount of conditioner as you did shampoo, emulsify and apply to the roots as before, building up if you need more.
Main image by ian dooley
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