Select the Substance node tab in the Attribute Editor, then click Export images to disk.
All Substance Output nodes connected to the Substance node (including both outputs denoted by green and orange icons) are baked onto disk.
In the Substance Bake to Texture that appears, select your map resolution and image format.
Note: mental ray for Maya does not support LZW compressed .tif files. To work around this, add IMF_TIFF_COMPRESSION=none to your Maya.env file. For more information on how to set environment variables using Maya.env, see Setting environment variables using Maya.env.
Select the Create shader network option to create a shading network with connections to the texture files baked from the substance output maps.