Trying to conceive a girl

Has anyone used a Chinese gender calendar? Or any sex positions other things websites tell u to do to conceive a girl? Like u can't have an orgasm etc. Has any of these worked for you to conceive a girl? I have 2 boys and I would like my next and last baby to be a girl. I know it sounds mean, but I really want one. But at the end I wouldn't mind what I have as long as it's healthy. But I would like to try. TIA