The Shape Guides are flexible, stencil-like drawing guides for drawing exact shapes, angles, arcs or lines. Use them to sketch partial or complete perfect shapes, and adjust them to any size, shape or angle.
 
When you activate a Shape Guide, you’ll see a number of features appear:
  1. The shape of the guide itself. The gray boundary is a reflection of the pressure/tilt bounds of the brush you’re using (based on your brush size) and is the maximum area that will fill when you trace the shape. Draw anywhere on screen to trace the shape.
  2. The circles (aka handles) of the guide. Touch a handle and drag it to watch the shape stretch or shrink accordingly.
  3. The crosshairs. They’re located in the center of the guide, and you can tap+drag them to move your whole guide without altering it.
  4. If you double-tap the crosshairs, each guide will respond with a special function:
    • The Line guide will limit your drawn stroke to between the handles.
    • The Arc tool will become a perfect half-circle.
    • The Angle tool will snap to 90 degrees.
    • The Ellipse tool will become a perfect circle.
    • The Rectangle tool will become a perfect square.
       
You can use the Fill tool to draw filled shapes and the masking tools to mask straight lines or shapes in tandem with the Shape Guides.
 
You can combine the Shape Guides with Measure to draw lines and other shapes with precise measurements and angles. You can see the Measure labels on your guide, and tap them to stick them to your plan. (As long as Measure is active, they’ll export with your plan, too.) Tap+hold a measurement tag to edit the values via keyboard.
 
You can also use Shape Guides to create floating measurements that aren't attached to a stroke or group for more general use, like adding a scale indicator on a drawing. To do this, set your measurement with the guide but don't draw, just tap the measurement and it will stay on your canvas. You can Select the label and move it around, and scale it like any other stroke.
 
For a beginning tutorial to designing with Shape Guides, check out our tutorial here.