klaas’s advice will only work if you have your keyboard set to international (which is easy to do). You can talso enter in the crappy alt codes:
á = Alt + 0225
é = Alt + 0233
í = Alt + 0237
ó = Alt + 0243
ú = Alt + 0250
ñ = Alt + 0241
ü = Alt + 0252
Note that you may need to turn on NumPad for that to work. See the instructions for switching your keyboard layout here.
turn on your language feature and when you switch to that new language it remaps your keyboard – now you just need to learn it. Or turn on your virtual keyboard to visualize it.