In case you want to create email accounts for your subdomains, you can add them to your plesk as a domain and then create your email accounts, following the instructions described below:
1. Log into myTophost Panel and then click on Plesk Login in order to connect to the Plesk of the plan that you are interested in.
2. In the tab Websites & Domains, click on Add domain.
3. In the blank field (1) enter the desired subdomain, leave all the settings on default and click on (2) ΟΚ.
4. In the Email tab, click on Create Email Address.
5. On the next tab (Create Email Address) enter the following:
-The name of the email account (e.g. info) and select your subdomain from the drop down menu.
-The password that you want for your email account (it must contain symbols, letters and numbers) (2).
-Confirm the code by entering it a second time (3).
-Click on ΟΚ (4).