If you have a double treadle wheel, setting off is a bit easier as if it goes the wrong way with one foot then you use the other.
With a single treadle, when you stop, get the wheel just past 'top dead centre' and it will automatically go in the right direction. TDC is where the two cranks are level at the back (I will have to go and check that on a single treadle wheel once the hens are in bed), but you can feel it as where the wheel is balanced ready to go in either direction. Like ellisr I learned to sew with a treadle machine but if you haven't then you need to practice. Try practicing without spinning for a while, just to get the feel of it. It won't be perfect for a while, but flicking the spokes isn't forbidden
If you are using unwashed fleece to spin it helps to do it in the sunshine or in front of a roaring fire, as the heat will help the fibres to run more smoothly. I find it easier to use washed and lightly oiled fleece to spin (baby oil on your hands is enough). I agree with ellisr too about not washing your fleece in a pillow case. Some fleece is less likely to felt than others but you are best to wash very carefully by hand, small amounts at a time, no agitation, warm water, minimal soap