Hello! Does anyone have any ideas for how to space...

Hey friend, So first i think with autos i would be careful with extreme training like topping super cropping or manifolding, unless the plant is performing beyond perfect. Your plants young enough to start making a perfectly even canopy through LST and defoliation (I'm a big supporter of cleaning up the bottoms of popcorn bud sites and drains on the plant) An auto will still stay relatively small especially with good, consistent lst. I'm sure it will double but perhaps look at other diaries of this strain to get an idea of the end sizes. I would ph often if not always..you can check the ph of the runoff and hope its stays consistent, but like the old saying says " an ounce of prevention is worth a pound full of cure." The better the ph stays, the happier the plant and the more available nutrients and less waste or problems to be fixed. Good luck with the training choices and happy growing ✌️