It's recommend to install cargo-odra first.
$ cargo odra build
To build a wasm file, you need to pass the -b parameter.
The result files will be placed in ${project-root}/wasm directory.
$ cargo odra build -b casper
To run test on your local machine, you can basically execute the command:
$ cargo odra test
To test actual wasm files against a backend,
you need to specify the backend passing -b argument to cargo-odra.
$ cargo odra test -b casper