You can get started writing tests in RapiTest's spreadsheet format easily using RapiTest's template test generator.
This creates template tests that you can fill in, so you don't need to start from scratch.
When creating a template, you can select the function(s) that you want to test, which will be included in the generated template. If you know the input values you want to provide for your test function(s), or return values you want to check against, you can provide these and the test generator will add these to your template. You can also set any configuration settings you'd like to apply to your tests, such as whether you want them disabled by default.