“Information on drawing requirements is based substantially on 37 CFR § 1.84. There are two acceptable categories for presenting drawings in utility patent applications: black ink (black and white) and color.

Black and white drawings are normally required. India ink, or its equivalent that secures black solid lines, must be used for drawings. Drawings made by computer printer should be originals, not photocopies.

On rare occasions, color drawings may be necessary as the only practical medium by which the subject matter sought to be patented in a utility patent application is disclosed. The USPTO will accept color drawings in utility patent applications and statutory invention registrations only after granting a petition explaining why the color drawings are necessary.”

You may check this out for standard of drawing:

http://www.uspto.gov/web/offices/pac/mpep/documents/appxr_1_84.htm

If you still dont know what it is, it is like someone have certain type of illness, the first thing to do is not to start study and get a medical degree, the first thing to do is to see a doctor.

If you have some invention that is important to you, get professional help from a patent attorney. If you do it yourself, you will only find out whether your drawing is acceptable by Patent Office or not 2 to three years later after filing.