Another way I use to suggest is to use an online spanish keyboard. Have a look at this link http://gate2home.com/Spanish-Keyboard and you will be able to write as the same as spanish keyboard and after make a copy and paste on text wherever you like. To use ´ click this key before the vowel one.

Try the combination of Alt+164 = ñ , Alt+165= Ñ, and other ASCII codes that you can easily find on Internet. That also works for French letters like ç.... If you are on laptop, then you should locate the numeric keyboard, sometimes you will have to press the "function" key along with alt and the combination of numbers you want. ( http://www.asciitable.com/index/extend.gif )

I followed the instructions here: http://tlt.its.psu.edu/suggestions/international/bylanguage/spanish.html After a bit of practice using it with duolingo lessons, I can now type them without thinking