How to draw on your screen in Windows
Windows has no built-in way to draw on top of whatever is already on the screen. The usual workarounds — pasting a screenshot into an image editor, or switching to a whiteboard app — both cost you the thing you were trying to point at. A screen annotation tool solves it differently: it puts a transparent layer over the desktop, so the application underneath stays exactly where it was.
Turn drawing on and off
The one shortcut worth learning first is Ctrl + Shift + D. It switches GlassNib between two modes, and everything else follows from that split:
- Draw mode — your cursor paints on the overlay. Clicks go to the drawing, not to the window underneath.
- Pass-through mode — your marks stay on screen but clicks go straight past them, so the application below behaves normally. Scroll, type, click a button; the annotation stays put.
That shortcut is registered globally, which means it works while another application is focused — you do not have to click on GlassNib first.
Pick a tool and mark the screen
The toolbar floats above everything and can be dragged wherever it is least in the way. Each tool is one chord away, all on the same modifier: Ctrl + Shift + P for the pen, Ctrl + Shift + H for the highlighter, Ctrl + Shift + A for an arrow.
Which one you want depends on what you are doing rather than what you are drawing. Freehand pen for tracing a shape as you talk. Highlighter when the text underneath still has to be readable. Arrow when you are pointing at something rather than joining two points. Rectangle to frame a region. Text when a number or a name has to survive being read back later.
Get back to work
This is where an overlay differs from an image editor. Press Ctrl + Shift + D again and the marks stay visible while every click reaches the application under them. You can annotate a spreadsheet, then scroll it, and add a second mark further down without ever closing anything.
Clear what you drew
There are three ways out, and they suit different habits:
- Eraser — removes whole strokes rather than pixels, so one pass takes the shape with it.
- Clear all — Ctrl + Shift + X, also global. The fastest way to reset before the next point.
- Fade delay — let marks clear themselves after a set time, from off up to forty-five seconds. The clock starts when you lift the pen, which is what you want while talking: the mark lives exactly as long as the sentence about it.
Keep the result
If the annotation is worth sending to someone, take a screenshot from inside GlassNib with Ctrl + Shift + S. It captures the screen with your marks already on it, so there is no second step in an image editor.
Nothing here needs an account and none of it leaves the machine — the drawing lives in the overlay until you clear it or save it yourself.