This section does not apply to the Mac App Store edition of DaisyDisk, because the latter uses Apple’s own DRM system, which does not provide free trials.
DaisyDisk comes with a free trial that you can use to fully evaluate the app before buying a license. In the trial mode, some functionality will be locked up until you register a license.
Right after you download and launch the app, you will see the following window, asking for your email address:
Please provide a working email address, because after you click thebutton, the trial activation key will be sent to that box:
Check your inbox and find the email with the trial activation key. Click the link in the email and DaisyDisk will confirm that your free trial has been activated:
Click thebutton to begin working with DaisyDisk.
See also DaisyDisk EULA for more detail on the terms of the free trial.