To create a new field press Add field on the first tab, you will then get a dialog like this.
Start of with giving the field a name, then Select extent, a world map (Google satelite) is now loaded to QGIS main window. Use the zoom tools (1. in the picture bellow) to zoom to your farm.
To zoom, left click (and hold it down) and drag, then an area is selected and when you let go you zoom in closer. When you have a good view over your field change “tool” to Add new feature (number 2 in the picture above).
With Add new feature activated left click in one the corners of your field, when you move the mouse you will have line from that corner, move the mouse to the next corner and left click, continue around the field like this.
When the entire field are covered right click anywhere on the map. (The field will now get a solid color). Now go back to the Create field dialog and select Save field, continue with the next field until you have painted all your fields on the map then press Finish.
Create the field as explained above, but before you save the field create the hole. Then left click on the “field name” in the layer panel to the left and get the layers properties. In the dialog go to the tab Symbology, and lower the Opacity to 50%. When you press ok now you are able to see through the field and see where you want to create the hole.
The hole is created with the Add ring tool, to find this you have to activate the Advanced Digitization toolbar.
Now you get this toolbar.
Activate (press) Add Ring and left click in the corners of the hole and end the a right click (just like when you create the field.
Edit a corner of the field, if you want to edit a corner of the field use the vertex tool 
and click on the corner that you want to move.
