How To Draw A Diamond? 

Step 1 - Draw lines as shown in the reference picture.

Step 2 - draw a straight line to combine

Step 3 - Now, draw a cross line as shown in the reference image.

Step 4 - Now, draw another cross line to make it look realistic.

Step 5 - Raw the final details in the diamond drawing

Step 6 - draw patterns in the diamond as shown in the reference image.

Step 7 - Add two shapes to add some decorative stuff to the drawing.

Step 8 - Fill light blue and dark blue shades

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