Understand basic structure.. Like circle.ical cylindrical.. And observe peacock's basic shape..relate to basic structures thay u know ..n u will do fine..ofcourse practice will simplify things..
1) Draw a small oval.

2) Bisect it with an angular straight line.

3) Based on the above line, create a triangle for the beak.

4) Make curved lines for the upper part of the body. (as in the 1st picture)

5) Overlap the body with a big vertical oval.

6 Overlap it again with another semi-circle at the bottom.

7 Create three small antenna-like lines on the head of the bird. (as in the 2nd picture)

8 On top of the antenna-like lines create 5 similar-sized circles.

9 Draw ray-like lines around the bird.

10 On the axis of the rays create water-drop like shapes all around for the feather patterns. (as in the 3rd picture)

11 Detail the feathers, patterns and all the other body parts. (as in the 4th picture)

12 Erase away all guidelines and add further detailing to the drawing.

13 Color the gorgeous peacock! (as in the 5th picture)