There are 3 ways to get this achievement:
1 - Die by a Raider using a Fatman - There are many of these types of enemies around the map but keep in mind that clearing out specific areas will make them safe zones and cause them to spawn more randomly. An easy place to find this raider is by travelling north from the
Skylanes Flight 1981, which is east of the Sanctuary and can be accessed relatively early in the game. North of this location you will find an antenna will this enemy, just go near and let them kill you.
2 - Die by a Super Mutant Suicider explosion - These are large green enemies that carry explosive bombs will red blinking lights. They can be found early on in the game at the
Medford Memorial Hospital or at a trainwreck south of
Diamond City (near Cutler Bend).
3 - Kill yourself using a Fatman or MiniNuke - Acquire one of these weapons and kill youself.