How i can drawing and save it as a layer.
Add jsfiddle example, but i need could i can drawing: http://jsfiddle.net/nieszka/Z7ABH
You can use layer.toJSON() to save the layer as string in the database.
layer.toJSON()
Check out: http://www.zeali.net/mirrors/html5canvastutorials/kineticjs/html5-canvas-save-stage-as-json-string-with-kineticjs/index.html
To create the layer again, use Kinetic.Node.create().
Kinetic.Node.create().
See also: http://www.zeali.net/mirrors/html5canvastutorials/kineticjs/html5-canvas-load-stage-with-json-string-with-kineticjs/index.html