How To Set Visible Time Of Your Snaps In Snapchat
You can change how long a snap lasts by tapping on the timer after taking a snap. Scroll down and choose from 1 to 10 seconds or choose the infinity symbol for you snap to last forever (until dismissed by the recipient).
How To Set Timer on Snapchat
https://www.youtube.com/watch?v=O_hX1mEbD-8