At the end of first lords fury, Tavi has the sentient fury known as Alera make Furycrafting available to anyone. He said that he wanted strength with furies to be based on merit.
The result of this is that all the races of Alera can learn to command furies. This is expressed primarily in the use of “tame” furies. Lamps, stoves, plumbing, causeways and all the enumerable mundane ways that Furies have been used to assist life in Alera are all examples of tame furies. This would be considered the least form of furycrafting. All humans and Icemen and most other individuals also bond to a personal fury. This personal fury is what allows the crafter to manipulate themselves or others.
For game purposes this means that if a player wishes to use a tame fury they merely need to say that they are doing it.