I know you don’t want to damage it but wanted to stress my point to really make you think. I have researched extenders myself and have one picked out if I ever decide to use one so I’m not against them at all. For me, I have decided to work on the newbie routine and modify it to my needs for the first 3 months. The plan is to continue using and modifying the routine until I do not see gains and then take a reconditioning break and start back up again with my modified routine. If no change in growth in a month or two then I will invest into an extender.
But that is me, I will still recommend that you avoid the extender for 3 months so you can properly condition your penis and then be able to maximize the extender’s effectiveness. If you do not see growth with the newbie routine in a month, tweak it. I measure every two weeks to see if I need a slight adjustment to the routine but I also monitor my PI to adjust my intensity/time of exercises.