If you are trying to conceive the best time is usually about a week before you have your period. During the week before your period you will ovulate and the egg will begin to make it's way to the Fallopian tubes. You can buy an ovulation kit or they have several free ovulation calculators online. http://www.fitpregnancy.com/ovulation/?gclid=CKiA8ZPg76YCFSJ0gwodNlJ_Fw
Count 14 days from the start of your period. That will be your fertile window and will last for 7 days. So if you started 2/1, your fertile on 2/14 for 7 days. Try during the 18-21 that's about when you'll ovulate. Good luck!