Step-by-step: Ensure you have correct perspective
1 To begin, I create openended triangles and consolidate their top- most points into one point. By clicking and dragging with the white arrow (otherwise known as Photoshop’s Direct Selection tool), I can drag the grouped points to where my first vanishing point would be. Doing so enables me to establish my composition’s horizon or eyeline. 2 I duplicate the first set of paths that I created and then, using the Direct Selection tool again, I select all of the top- most points. By holding down the Shift key, I ensure that I translate them horizontally, keeping them constrained to my horizon line. This, in turn, gives my composition its second point of perspective that I can now follow as I begin painting. 3 I use the white selection arrow to manipulate the paths to act as guides, drawing underneath them. However, if your paths are visible and you attempt to transform something, Photoshop will try to transform the paths. One solution is to stroke the paths into a new layer, giving you your lines of perspective in pixels that can be made semi-opaque by adjusting the Transparency. 4 Paths can be assigned a name and then duplicated in the Paths window. Should you need vanishing points for an object that’s neither parallel nor perpendicular to your initial object, then one solution is to duplicate the paths and then slide the two vanishing points horizontally across the horizon line. This adjusts the guides to their new application in your composition.