As you make a Sign, bending your middle finger and letting the other fingers spread, a telekinetic blast comes out of your hand. Each creature in a 6-foot cone must make a Contitution saving throw. A creature who fails is pushed 4 feet away and will be left prone. The blast pushes away any small thing that isn't being worn or carried.
At higher levels:
When you cast this spell using a spell slot of 6 level or higher, the creatures in the area of effect must make a Dexterity saving throw. If they succeed, they'll just be pushed 4 feet away and left prone. If they fail, not only they will be pushed away, but they will be left frozen and incapacited. The prone condition will not apply if the creatures fail.