Lots of women don't subscribe to the base coat/two thin coats of colour/top coat school of thought when it comes to nail varnish application. And that's a-OK with me; I'm not a beauty Nazi by any stretch of the imagination. But if you are trying to follow this three-step rule, you need to know your base coat from your elbow for it to work - you wouldn't build a house and expect it to stay put without having laid the appropriate foundations, like.
First things first: when people talk about applying a base coat, they do not just mean simply popping on an undercoat of any common-or-garden clear or light pink nail varnish. A base coat is a specific type of product, and no, it's not just a money-making malarkey dreamt up by scheming marketeers trying to squeeze every last cent out of you.
A good base coat that's specifically formulated as such will act as a barrier between your nail plate and dark or strongly pigmented polishes, protecting nails from staining, discolouration and yellowing. It will also provide a key or grip for colour to adhere to, thus helping to prolong the life of manicures. Some base coats will also fill ridges, giving a smooth finish so nails are less prone to snagging and breaking.
Generally speaking, base coats are transparent and will dry to a matte, dull or tacky finish to give nail varnish something to "stick" to. If your nails are in need of a bit of TLC, try a treatment base coat - it'll contain things like aloe vera, calcium, vitamin E, or protein to condition nails.
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