I was going crazy trying to keep the buttons still while I sewed them. I like to sew them on the sewing machine with the button foot and putting a bit of sticky tape just above or below the holes works perfectly.
I taped all these buttons on at once then hand sewed them all at once running the thread down behind between the buttons. I wasn't sure how the knit would go on the machine.
For woven fabrics I tape and sew one button at a time on the sewing machine.
This is not an original idea but I have only seen it published once so I thought I would share it now I know it really works.