SET COUNTDOWN TIME
You can easily set the countdown time by mouse, a digital panel will be shown when you mouse over the digits of hours/minutes/seconds, and then just click the button what number you want.

START/STOP/CLEAR THE TIMER
You will find START/STOP/CLEAR buttons at the bottom, double click the blank area to hide or show panel.

• press START button to run and hide button panel after you set time, it will be twinkling, playing alarm sound and show button panel when time is over, if no time set, the operation will be ignored.
• press STOP button to stop/pause the timer, you can set and/or continue the timer by press Start later.
• when timer stopped, press CLEAR button to stop twinkling, playing sound, and reset to 00:00:00.

Switch to full screen mode anytime by pressing the F11 key in Windows, or use Shift+CMD+F key in Mac OS X.