Question for native Spanish speakers
¡Hola! As a native English speaker, I have trouble remembering when/where to put accents. 
As native Spanish speakers, do you ever have trouble with accents? Probably not, right? 
4 Answers
I am very careful with my orthography, and although the rules are not really that complicated, they are not that straightforward either, and many educated Spanish speakers miss them too frequently sometimes. The important thing, as Guillermo said, is to know where the stress is, and how to split a word into syllables (there are also fixed rules for this); after that, if you are not sure, apply the rules step-by-step:
1) Is the stress beyond the second-from-the last syllable? (e.g. in "po-nién-do-se-lo", it is the 4th from the last) Then put accent on the syllable right away. Exception: for word ending in -mente, you apply the rule as though this suffix was not there at all.
2) Is the stress on the last syllable? Then, if the last letter is a vowel, N or an S (both preceded by a vowel), put the accent there; otherwise, don't.
3) Is the stress on the penultimate syllable? Then omit the accent only if the last letter is a vowel, N or an S (both preceded by a vowel); otherwise, put the accent.
4) There are a small group of words (e.g. tú, él, mí, cuándo...) that require the accent or not depending on how they are used. However, the ones with this special accent (diacritic accent) are pronounced with stress, while the ones without the accent without stress. Foreigners may not notice the difference, but pairs like "tu" and "tú" do not sound the same, for example. Ask a native to read slowly for you "Tú tu espacio y yo el mío".
You're worried about when/where to put accents, huh? You should join my club and enjoy forgetting not only accents but whole words.
Don't be harsh on yourself! Using accents is a skill that gets better with time.
Sometimes because the computer (I don't know how to put the accent). But I learned it when I was in the school. Maybe you need to read and practice your Spanish lessons.
If you know where the stress goes on the actual word, the rules for whether to place the tilde or not are really simple.
So in my case, the answer is no, I don't have trouble at all.
