Decorating/stenciling crusts

I was recently in Tucson and a fabulous bread that had on the crust a shape of a cactus made from a stencil made in that shape. I know ( or think ) that you sprinkle flour over the stencil, once the loaves are about to be put into bake, which then lays on top of the bread and never gets cooked but the shape remains on the finished loaf

Can someone kindly tell me if this the correct/best way to do it ? How do you retain the finished shape when the bread is finally baked and has cracked from baking ? My first effort I forgot to use my lam so when the bread cracked it made the form disappear ( fortunately not the taste; I was baking the 100% Sourdough Spelt bread which is my favorite so far ).

Does any know where one can get stencils ? I know that you can always order them from Amazon but am wondering if there is a store that is better suited to having them, like a crafts store for example.

Many thanks in advance for all your help.

My approach with decorative scores, which could be applied to stencils, is to direct the rupture of the crust with deep cuts, so your “palette” of pretty escapes the force. See pic below for what i mean.

Here are stencils from the Breadtopia store

In a pinch, i cut parchment paper myself, like in the rugbrød recipe i wrote here.

Many thanks for all the info about stencils and bread crusts…really appreciate it and will try as you suggested next bake.