are they a new type of work shoes,
this must be your home surelly.
as said, stand back and lenghen your pole out, keep comfortable, stress on the shoulders, get a swivel neck, then the brush changes direction on the glass,
look on thr Gardiners web site , look for Videos, or look in the brush section and it will show you.
are you using pure water.
we all have to begin new techniques to make the work easier, it will come with confidence. learn how to clean the ledges also, this is where traditional cleaners score points, they just wipe sills down with a clith.