Hire an artist.
Pixel art is actually a very tricky form of art if you want to make anything actually look good. You have to be very meticulous and pay attention to every detail. You have to also have a good understanding of anatomy/shaping as well as lighting and color patterns.
Not that it isn't difficult, but the creator of Papers, Please pulled off programming, music and art apparently all by himself. I think it's possible to create expressive pixel art with some dedicated practice.
Like learning anything new: start with the simplest project you can think of, be prepared for frustration, and show your work to people who will encourage you.
