12. Limitations  If you now decide to modify the grid, such as move the vanishing points, then any symbols or text you’ve used would become outlined. You can set different perspective grids on multiple artboards, but again doing this will outline symbols and fonts on the first grids you made. This may not be an issue for you.

13. Pattern problems  Patterns are a challenge for perspective drawing. If you fill a shape with a pattern, it will not conform to the perspective grid. Workarounds could include rasterising the pattern in Photoshop or trying Illustrator’s Envelope Distortion – though the latter option makes for a heavily compromised look. 

14. Finishing touches  Illustrator’s perspective drawing is not 3D modelling. As such, there are no lighting effects. Instead, try adding a gradient fill to one side of the box. Here, the Convert Direction Point tool has been used to bend the box lid for added authenticity and a shadowy blue fill under the lid suggests a flap.