From what I read extending isn’t about stretching the shit out of your dick, it’s about gently keeping your unit elongated under (very?) LIGHT tension for extended periods to promote cell division or whatever it’s called.
I just got an extender too and am going to sit at 600 grams, not moving the tension screws, for at least 3-4 weeks, possibly much longer. First 2 weeks I will do 3hrs per day with 5 minute break every hour to 1.5 hours. Then I’ll be going to probably 6 or 8 hours then eventually 12 if I can. NOTE: It’s important to check your glans regularly and if it’s cold (cool is ok) or numb take a break and massage/kegel your unit back to health.
My starting length on the extender will be my BPEL minus approximately 4cm. The first 4 or so days I was using my max BPFSL, not fun at all!
Here’s a couple bits and pieces I’ve been reading. Note that there might be some conflicting info but that’s up for you to sort out. EDIT: Can’t seem to find all my links, I’ll post if I come across them.
SUPER DOUBLE EDIT: I see you have a pic up, you really should have got the new type extender with the cradle and noose. I find the cradle helps to alleviate some pressure on the glans. Also if your extender didn’t come with a foam pad to put around your glans before it goes in the noose you can wrap it with something soft.
Also to make the extender longer and apply tension you turn the screws at the bottom of the extender while holding the cylinders above the hexagonal parts so the parts don’t unscrew. From your pic it looks like your are holding the screw while turning the hexagonal parts.
I do this one side at a time for about 5 turns so the device doesn’t unscrew at the rods and doesn’t bend the rods.
Also be sure you are fully compressing the top part of the extender (noose end) then fixing the noose around your glans.