Well, can I ask what you've done so far in terms of putting your comic out there?
Have you promoted your work on other places (the forums, social media, other inner groups)?
Have you networked with other creators, maybe even promoted someone else or have given feedback?
My advice is to make a presence online. Because Webtoons is oversaturated and is a BIG comic-hosting websites, many comics get lost in the sea. But, often enough, it helps to create a presence online, where people recognize you and your work. Now, getting noticed by Staff can be a bit of "luck of the draw". There have been people who were noticed after they were updating for 2-3 years, and there are people who've been noticed when they've been updating 2-3 months.
But, for what I've done, I did networking and promotion.
I promoted my work on my Twitter. I showed my WIPs and my art so that people can be hyped up. I've also built connections with other artists, finding friends along the way, and some of those connections have resulted in some promotions (both for them and for me). As a result, here's where I sit now:
Now, I'm not noticed by staff or a featured creator. But I have a nice fandom, and people are excited for my work. And I think a lot of that comes from being hyped up and being a bit familiar with my works.