Id leave my home with all of my belongings, i wouldnt take my phone or anything. Also, id do my makeup and dress nicely.
Id leave letters for my friends and family, i want them to know that it wasnt their fault and so they can get over quickly.
Go leave my ex boyfriend a birthday present i bought and a letter for him in front of his door.
Maybe buy myself some last meal or sweet treat, try to make it peaceful and pleasant.