Drawing a cartoon monkey face is quite simple, actually. You just need to know how to make use of line drawing techniques.
First, picture in your mind the contours of a monkey; do not extend your imagination to the finer features of a money, but rather just focus on the outline.
Next, try putting that on paper. By now, you will agree with me that going by its contours, a monkey is mostly round in shape, or that you can draw an acceptable figure of a monkey with a few circles.
Now, take a plain sheet of paper and a sharp pencil with not too thick lead, and draw an oval shape in the center of the page. On either side of the top end of the oval, place two smaller circles. These circles must appear to be sitting on top of the oval, just a little inside the oval line. For better results, you may draw a thick line for the oval and draw comparatively thinner lines for the smaller circles on top of it.
The smaller circles must be drawn in such a way that they touch each other on top of the oval. By now, there should be three points where the drawings meet. With the help of a clean eraser, wipe clean the joint portions in the small circles on top the oval, stopping short of each circle leaving a trace. To get some perspective to your drawing, you may lightly draw one full circle quite close and one that covers all three - the two small circles on top and the oval in the bottom. Note that you will have to wipe clean portions of this circle later, so, do not use any permanent markers; you should use only a pencil. Always have a clean eraser handy.
Next, wipe clean all the inward meeting points inside the circle, i.e. the two on top and on the bottom, along with any other unnecessary lines in between. This should now give you the face of the cartoon monkey.
Time to do some filling in, but before that, draw two circles on either side of the perspective circle and these will form ears of the cartoon monkey.
Now, fill in this face structure with a small circle to form a nose toward top portion of the outer circle. Draw the circle in such a way that it is incomplete, do not make the ends meet and then draw a smaller inverted half circle inside so as to form a nose with two nostrils.
Place two dark circles for eyes on top of the nose. Place a smiling half moon below the nose and voila - cartoon monkey outline is ready.
Now, to fill in - either use colors or black and white. Use dark brown crayons and fill in the outer edge to form the face, the inside area can be filled in with a skin brown color or a sky-blue shade. Fill eyeballs with dark black and you should have a cheerful cartoon monkey face smiling back at you.