How to keep a motherplant

Ok, i have some purps plants and i intend to establish a strong mother and keep cloning. Are there any ways to stall the plant so its not growing upwards really and is just bushing?? ( other than going low on nutes, and side lighting). Also where exactly do you take the clones to make it so that more will keep growing, i clone a plant before and clones only grew only the nodes above where i'd taken clones. Last but not least, i've heard sexing your plant makes it lose potency ( perhaps thats after the first sexing) but is this case? im hoping its just a myth otherwise it would be a contradiction of the idea of sexing your plants and establishing a mother hahah.. thanks

holy questions, ok first top you plant to shorten and bush it out. you basically cut its head off. in doing so also get a perfect first clone! also, train them to grow to how you want. in doing so you tend to strengthen the stems and also convenience yourself with the size and shape you want. hope this helps