If I cross an auto with a regular will it keep the auto characteristic? Which should I use for male and female? The auto or the regular?
You should use a male AUTO to pollinate your female plant. You will get seeds that might be 50/50. When you find the auto plants from those seeds then try to identify an auto male and auto female ASAP and cross pollinate the two. Only then will you have 85% AUTO FLOWER seeds for your grows then on. If you have a female AUTO then you want to get a FEMALE clone and grow it to maturity then use the colloidal silver method to turn the female clone into a "Hermi/Hermaphrodite" and let it pollinate your female auto. This will give you a good chance of 85% female plants and a 50/50 chance some will be females auto flowers.