You can always preview your message prior to sending, but if you would like to see it on your own phone or email, you can also send a test to ensure your message goes out how you intended it to.
Select the student and guardians you want to message, draft your message. You can select email or text. Then prior to sending select the drop down arrow next to "send" and select, "send test".
Then you can input yours, or others, email or text (depending on what you have selected) and change the language as well, and click "send". This will not go to the guardians, it will only go to the email/number you inputted.
The test messages you will not be able to reply to, and the message will be simplified.