One way is to go to the “Add Friends” page. Here, scroll down to the Quick Add section, and you can see that Snapchat will suggest users here and often shows an approximate number like “3+ Mutual ...
Snapchat always alerts someone when you screenshot their Snap, but there are ways you can get around that.
You can delete your Snapchat story before it automatically deletes after 24 hours. Here's how to delete a Snapchat story on an iPhone or Android.