what positions you like to shoot from

Any position that might occur in a realistic scenario I practice. Prone, no support. Prone with support. Sitting, kneeling, on side with improvised rest. Standing using trees or fenceposts. Sitting with sticks or other rests. Standing freehand. Pehaps a half dozen more similar conmbinations. If you hunt varmints (all kinds) you need to be ready for the scenario that presents itself.
 
I prefer to sit in my car and shoot out the drivers window as the birds don't scare when you're in a vehicle just as long as you don't move too much.

When I'm on foot, I prefer to rest the rifle on a trigger stick tripod, short version, and I either get on my knees or sit down while using it. If I don't have the tripod, I will look for a tree, fence post, gate, side of a building, etc. to brace the gun against.

My favorite method is off a bipod on the roof of my car where I can brace the front and rear of the rifle for a solid and steady shot.

I'm a terrible off hand shot.

I would love to shoot prone but in pastures and on the farmyard it's just not a good idea.