Courtesy of redefiningstrength.com:
To do the Dumbbell Squat to Press, grab a dumbbell in each hand and bring the weights up to your shoulders. You can hold the weights with your palms facing forward or with your palms facing in toward each other.
Holding the weights at your shoulders, squat down sinking as low as you can. Then drive back up to standing and press the weights straight up overhead.
Make sure you don’t go forward as you squat down. Also make sure to press the weights straight up. Do not let your arms go out wide or all over the place.
The more you use your legs to press, the easier it should be on your upper body to press the weights. If you want to do a stricter press, squat then stand up and press once you are fully standing.