How To Conceive Fast?

hi i m 25 yrs old and 2yrs of marriage.my wheight is 43 and height is5.2.we were taking precaution for 1 and half year.we ara ttc.last month i have pain in lower side of back before10 days mensus due.then i have consulted to gyene doctor,she reccommend me folic acid i.p 5mg.after that my mensus have come.what should i do to concieve faster.