When I previously attempted I had a schedule email ready with a final message to family. I included a little section about my few possessions and who should get what, but I mostly left it up to them. Perhaps I'm asking for too much, but I do hope that my stuff ends up in good hands instead of just sold for a quick buck.
And I think in general giving your belongings away before you attempt/succeed might be a bad choice.
1. You could survive and the shitty situation would feel even shittier after you gave everything away. (Tho I guess you could ask for it back if given away to loved ones)
2. Randomly giving stuff away would look pretty suspicious imo. Especially if those loved ones are aware of any history with depression and suicidal thoughts.