Graceplus,
It really depends on your menstrual cycle to determine when is the best day to make baby. You need to know when does your ovulation take place to maximize your chance of conceiving a boy. You should go to Watsons to buy the ovulation test kit to find out the day of ovulation.
If you make baby too soon before you ovulate, the y sperms although swims faster than x sperms, survives shorter than the x sperms. They cannot survive long enough to wait for the ovulation. Therefore, you should make baby within 36 hours after ovulation to increase the chance of having a baby boy.
Thank you all your suggestions, my heart is really up and down. I know that we cannot to make the decision to have boy or girl for our life. However, I think it is normal if I have a girl, then I want to have a boy. May be I should be relax no matter the coming baby is boy or girl, he/she is my baby...
Graceplus,
Don't hesitate, go and buy the ovulation test kit at Watsons. Not only increase your chance of conceiving a boy, but also increase your chance of being pregnant. What not give it a try?