• Sailormoon has two distinct styles: anime and manga. The anime style looks great if you're a very precise artist, or if you color and touch it up on the computer. For me, the bold ink lines and everything were always a pain in the arse. I focus more on the manga style, since that style lends itself to the things I work with.

• Sailormoon eyes are pretty basic and unique, especially in the manga. Check out the pic below of a basic Sailormoon eye:
  

  This is even more basic than the SM anime eye. You have the usual 1) top line (which can vary depending on the character, but is basically the same in the manga), 2) main eye part (this varies too), 3) and bottom line. The 4) crease is a lot more pronounced in the manga, but the 5) eyebrow is less so.

• There are basically three types of people in the Sailor World: older people (parents, negaverse targets, and even the outer senshi), younger people (main/love interest characters, inner senshi), and annoying little kids (like the pink parasite known as Chibiusa). Eyes get thinner from top to bottom for more mature people, and taller and more vacant for younger ones.

Good References:

Darkstar's Sailor Moon Go here! He has drawing tutorials for almost everyone in the series! And he's got a warped sense of humor, just like I do.