I would think you would not have a cola inless it is in the flowering stage. It is gonna double in the flowering stage so you might wanna top it and put it into 12/12 light. To top just cut it at the top under the last node. I have cut them in many ways some by mistake and deer have topped plants for me as well. I have never seen any die from being topped the wrong way they will always grow back. Inless you top it at the bottom node!. Just cut the top node off above the top pair of leaves.Also if you are not sure look under grow facts or google it.