I’ve struggled with this for a while too, and I’ve found that the only ‘secret’ is to go to sleep earlier so that you either wake up earlier, or wake up feeling more refreshed. You should also do this in conjunction with getting up and out of bed as soon as your alarm goes off. I’ve got an alarm that doesn’t turn off until I go into the kitchen and scan a barcode because otherwise I’ll turn the alarm off and go straight back to sleep. Someone also suggested opening your blinds which works really well if you don’t need the privacy and you wake up after the sun rises.