That's a good question.
First: maybe i can tell you al lot of thing but if that "one day" will come . . . well, maybe i do all of that things. .. or maybe i do nothing.
But, i think in this things:
1.- Say good-bye to all my friends.
2.- Eat, a lot, all my favorite food, is better to die with full-belly. xD
3.- Writte a letter to my parents . . .and my bros and sis . ..
4.- Say "I love you" again to that girl. . .
5.- At the end. . . well, drink, maybe tequila, vodka. . . whisky and loss the last minutes happy. . .with the better company.
That's my last day. . . crazy!