Watching and enjoy the work of Joao Carvalho:

3D Doodles By Joao Carvalho Seem To Leap Off The Page | DeMilkedwww.demilked.com/3d-lines-notepad-drawings-joao-carvalho/

1. Find or draw an image of an object having three dimensions. Toy characters are good because they are very recognizable and made from simple three dimensional forms.​ If you want to trace an image, follow the directions below.

2. Copy the image and paste it into a Word document. Size the image up to fill the page. If the image is still not big enough ( it should fill most of an 8.5 x 11 inch paper) then you can zoom in on it in Word using the zoom feature on the lower right corner.

3. Trace the image lightly on a piece of copy paper. Once you have it basically traced, you can remove the paper and make any needed corrections or adjustments. 

4. Draw you straight lines first. The more detailed you object it, the closer your lines should be. Use a lined piece of paper to help you make tick marks on BOTH SIDES of your paper. Draw your line in blue color pencil and connect tick marks on both sides to make straight lines

5. Draw the bump lines. Start with the lowest easier ones first, then more to the higher more complex bumps. The higher the curve = the bigger the bump.

6. Fill in the shadows to make the form look more three-dimensional. Convert your reference photo to gray scale so that you can see the shadows a little better. Copy the shadows or imagine where the shadows would be in the bright sunlight.