There are two versions to this model. One with the helmet interior hollow (DeathTrooper) and the second version being completely solid (DeathTrooper_Solid).

Print Settings

Printer Brand: Ultimaker
Printer: Ultimaker 2
Rafts: Doesn't Matter
Supports: Yes
Infill: you choose

Notes:
Print as you see fit really. Supports are a must i would say though (at least touching build plate), maybe use a raft too for extra assurance of model stability when printing.
Infil percentage is your choice also. I would say a minimum of 5% depending on the size you want to scale it too.