My previous attempt was a failed hanging which happened very sporadically. Wasn't planned, it was an act of desperation. Like jumping out of a burning building. I knew I just had to go. Which isn't much help to the question if you're actually planning rather than being pushed.
I think the reason I am so calm with my planned death now is because of a variety of reasons. I fucked around a lot with psychedelic drugs in my mid 20s. Experiencing ego death, regularly doing dmt, all these things felt like chasing and staring into the void. Experiencing the nothingness that I think is like a preview to death. I loved doing that.
I also did a lot of studying into spirituality, Zen Buddhism, things that at the time were trying to help me find a reason to live, but for me now, actually have made me comfortable with the idea of death. Thinking that there could be something more to this after life, or maybe there's not. Either way, none of this matters. We're here for the blink of an eye in a universe of a scale we simply cannot comprehend.
I could go on, but I think the best advice I can give was something a friend shared with me back in the days I was doing psychedelics and experiencing ego death.
"Just let go."
You'll likely feel terrified. Death is pretty scary, it's the ultimate unknown. You'll want to hold on to your ego, to your life and your memories, because they're all you've ever known. But follow your heart. Take that step into the unknown. Embrace it. Feel the excitement for the unknown and what comes next.
Just let go.