Imac as second display
How do I use my Imac as a second screen - and connect it to my windows laptop?
How do I use my Imac as a second screen - and connect it to my windows laptop?
As Dennis mentioned you don't, please read Use your iMac as a display with Target Display Mode .
We know it's not what you wanted to hear however it's correct information.
You can not use Target Display Mode or a cabled display connection.
You will have to use a Virtual Network Computing App like ScreenRecycle, RemoteDesktop or VNCViewer.
Imac as second display