I know it's not what you want to hear right now, but if SH doesn't feel as fulfilling as it used to, maybe it's time to take that as an opportunity to try and stop?
Nobody here should be giving you tips on how to cut deeper. You want advice? Make sure your wounds are clean, make sure your blades are disinfected, don't go giving yourself sepsis or tetanus. Try out the rubber band method or maybe smoke some weed, lol. I've been cutting since I was like eleven and all it's given me is nerve damage, infections, and awkward conversations over scars. There's nothing that makes it "worth it", especially when you're constantly escalating and doing worse and worse damage