Our crafts studio and restoration workshop makes duplicate antique restorations, old tile plinths, murals, and all kinds of ceramic reproductions. We use different techniques used in tile painting.
One of the techniques used for restorations is the stencil. This technique consists of covering the tile with a template already cut with the pattern shape in it. Then artist brushes over the template with one colour (one colour per stencil at a time) tile by tile, manually, and process ends by firing the decorated tile.
In this image you can see the different phases through the painting templates:
And here is an example of an old tile duplicate (original-right, copy-left):
Other examples of tiles, in this particular case used as a modern solution in patchwork style:
Another example of a restored old tile plinth:

Another example: