In your case, since you have a cinnamon morph already, to make more snakes that express the cinnamon gene you would just need to breed your snake to any other snake. Cinnamon is co-dominant, meaning that only one copy of the gene (or one parent's contribution) needs to be present in the offspring for them to be cinnamons, so if you bred your cinnamon to a normal, it would be most likely that you would also produce some normals that are plain normals (not het. for anything).
Cinnamon is a base morph, meaning that sometime, someplace in the world, a spontaneous mutation occured and then survived to make offspring. I don't know the specific history of the cinnamon gene, but that story COULD sound like: "There once was an African import that looked like a cinnamon, and then it's looks passed on to it's offspring in a predictable, non line-bred way..." Base morphs can be combined with other genes to produce combo offspring, but you can't find the genes to "make" a cinnamon, you must purchase one or have it result from a cinnamon pairing.
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