You will first need to install Sylo (for instructions, see the article 'How to install Sylo').
You have the option to join from the Sylo desktop or mobile application.
Open the Sylo application and login - Use the email and password you chose when registering.
Once logged in, you will see the person who invited you in your contact list.
Click their name to enter their profile page. From there you can confidentially video call, audio call, share files or message them.
If you are signing up without any contacts, please see post 'How do I invite my contacts?'