Here is a Video from Microsoft about scheduling a meeting in Skype for Business (1 minute 49 seconds).
This is the best way to arrange tutorials in Skype for Business as it doesnt rely on having the other person as a contact and offers several ways of joining the 'meeting'.
- New Skype meeting in Outlook*
- Meeting options
- Changing default settings for large or confidential meetings
- Free web app
*A meeting can also be set up in the same way in the Office 365 (online) Calendar except that the Skype for Business option is available after you click ‘New meeting’
Please note the the telephone keypad is not available in the student version
The same video accompanied by written instructions (scroll down the page)