I find it very easy to do in the car. I have all my pieces cut and in plastic bags in my small sewing kit. You only do one seam at a time and I have a small swatch of material that I pin to my shirt and put the pins I'm using for the pieces in it.I have small scissors on a lanyard. The only thing I do much different when I'm in the car is I load one needle at a time, where as at home I generally load four or five. I may look a little nutty when I forget to unpin the cloth on my clothes and go in somewhere to eat. Hand piecing is so much easier that machine piecing, it just takes lots longer.