Hey its August already!
The Farmer uses a huge machine called a "Combine Harvester" - I'm sure you have seen them in the fields.
The Combine Harvester travels up and down the fields to harvest the wheat. It chops it off and it is then sucked through to a rotating drum which separates the chaff (the straw bits) from the wheat.
The wheat is put into a large tank in the Combine harvester and the straw is either blown back onto the field to be ploughed back in or it is rolled up into huge round straw bales which are sold for animal bedding/food.