SCROG question

Greetings,

I am very interested in trying a SCROG grow. My one concern is that I do not use clones but always start with soil and seed....

What is the best approach for starting with seed, but yet one may not have determined male from female plant until a 12/12 cycle begins.

Is it not difficult to allow both male and female to grow together before determining sex?

Can the screen be added once sex is determined so that you do not allow male plants to be intertwined with female plants?

Any tips for a seed grower would really be welcomed....what's the easiest approach for determining sex as a plant being female and then adding the screen so that all males are removed prior to them being intertwinded with females. I do not want to be removing males that are locked up with my females in the screen...

Please clarify or provide me with some guidance in regard to the sequence that I should follow...

Thank you...