There's one beauty question I get asked way more often than any other. It's not about what foundation I wear, or how I wash my face at night, or even my favorite lipstick. It's "what falsies are you wearing?"
But truth be told, I rarely ever wear false lashes. In fact, I kind of despise them. And I've never been asked that question on a night I've actually mustered up the patience to wear them.
This is going to sound like such a stupid humble brag, but most people are astounded when I tell them what I'm sporting on my eyes in nothing but mascara. Sure, I'll admit my lashes are naturally on the longer side thanks to genetics — but their eye-turning length is mostly due to a simple application method you'll kick yourself for not knowing.
This mascara trick doesn't require a specific kind of mascara, but I'd generally suggest using one that's formulated for length rather than volume. These are my two favorites.

Why length over volume? It's just plain easier to build volume with a lengthening mascara — which you can do by applying extra coats near the base of your lashes — than it is to achieve length with the fluffy applicator of a volume-specific one.
Its applicator is perfect for building length because its has tons of short bristles that can grip lashes tightly.

When I want something a little more bold, I reach for Benefit Cosmetics BADGal BANG! Volumizing Mascara ($25, Sephora).

It has an extremely similar applicator to Glossier's (this style of applicator is the common denominator of all the mascaras I like), but the formula itself is fibrous and sticks to itself enough that it can practically build new eyelashes for you.

For the purposes of showing you how I apply mascara, I used this one.
Here I am pre-mascara. When bare, my lashes are practically invisible despite being pretty long.

And here is how I've noticed a majority of people apply mascara: Outwards.

I think people fault to applying mascara this way because it seems like a no-brainer to follow your lashes' natural direction.
Brushing the lashes outwards will make them look... nice, but not nearly as coated, full, and long as they could be.

And that's why I apply my mascara upwards and inwards, especially near the inner corners.

I also make sure to wiggle my applicator back and forth the entire time to fully coat each lash.
Now that's more like it.

The key difference between a pair of real eyelashes and a pair of wispy falsies is the amount of volume that's visible in the inner corners and the direction of those lashes.

Getting into those corners with your mascara wand is the number one way to make those real lashes pop.

It might seem like a small difference, but trust me, people notice it. Plus, it'll save you all the discomfort of a pair of fake eyelashes.

It's really that simple. No go out into the world and use those lashes of yours for good.

You know, like SpongeBob would.