Hi Mumzy, i have heard exactly the same as you, back and forth for boy, circles for girl and over the belly when preg and over the hand tp show all babies

It worked for me for my first preg, a little angel boy i lost at 18weeks,
and worked again for my girl, who i lost at 36 weeks and when i do it over my hand, they both show
I'm preg again (fingers crossed) but i havent done it yet coz i am only 8 weeks, and even though i know that genes determine sex and its already decided, i will wait till the age that they are formed to try it!!