Some more TURBO questions

Alright, hmmmm im starting to get this turbo knowledge down pack but i still have some loop holes to fill.Alright what type of things can you do to your engine to ensure that your engine wont blow out or have any complecations due to a turbo(basically how can i make it strong and take more psi) and does the turbo work all the time as you drive or only as you get to higher speeds or something like that. Im guessing it casual makes your car faster.....