My Plant :) just starting, my second grow, first indoor, advice would be cool

so i have 8 sprouts that are four days old under 4 23 watt 5000k cfl bulbs in a closet. But i am only planning on keeping one plant, they are just from mids and i want to make sure i have a female to grow. I have to have the bud ready to blaze by august 15th, any advice on when i should start the flowering process, if my lights are good, and how to determine whether the plants are male or female before you start to flower. i would put up pics but i dont think they are really necessary since they are just sprouts and my closet is pretty basic, i painted it flat white inside.

thanks for any advice