✔ 最佳答案
Firstly put it on charge for several hours.
If the battery has gone flat since it was last used, it will not do anything until it has a reasonable amount of power in it.
Then, press and hold both the home and power buttons.
After around 10 - 15 seconds, it should hopefully show the Apple logo on screen. Let go the buttons and see if it boots up normally.
If you can't get it to work, it most likely has some internal damage.