Attached to a fucking machine is definitely best. Attached to a strap on harness would be better, I bet. If you don’t have a fucking machine, try a ball. It could be smaller like a volley ball or larger like a yoga ball. With a smaller ball, try placing it against a wall just below your ass with your upper thighs against the ball. You can slightly lower and raise your body, rolling the ball between your body and the wall, causing the dildo to fuck you.
You can also attach it to a door. Use a bungy cord on one side of the door and a rope on the other.
