I've been practicing drawing humans this past year, and when I discovered this particular way to draw a nose, I stuck with it.
What you will need:

-Any type of paper, whether it be printer, card stock, to 150 lb. watercolor paper. It really depends on your preference.

-You can use any medium of your choice. Personally I have only used graphite and colored pencil for this, but feel free to experiment to your hearts desire!

-A blending stump/ totillion. (You could also use your finger for this, but it will be especially difficult for a small, dainty nose)

Step 1: Draw a Triangle

For the first step, you will see here that I lightly shaded in an inverted triangle where the nose should be. This is the base shape of the nose. The top of it will be where you put the nostrils.
Depending on your style of drawing, you can place the triangle higher on the face or lower, as well as draw it smaller or larger.

Step 2: Blend It All In

For the next step you'll be using your blending stump. It's rather hard to explain this step, so I'll do my best.
Take your tortillion and blend the inside of the triangle. When fully blended, make circular motions around the top of the triangle until you get the affect of a little button nose, or the shape of nose you want. You can leave a small spot blank for a shine if you prefer. I think leaving a shine adds to the 'little button nose' look.

Step 3: Adding Detail

After you've got the second step to your liking, now you can place and define the nostrils and the outer parts of the nose the way you like.
There is no limit to adding the details when drawing.