If you are using a Mac, you can put an Irish síneadh fada (´) on any vowel by pressing option+e first, then releasing those keys, then typing the vowel you want the síneadh on (the option key may be called the 'alt' key on some keyboards):

option+e -> (release) -> a = á

option+e -> (release) -> shift+o = Ó




For the Scottish Gaelic lengthener (`), use option+_ instead of option+e.

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Múinteoir Gaeilge - Irish Teacher
My "specialty" is Connemara Irish, particularly Cois Fhairrge dialect, but I can also speak Ulster and Munster Irish with native-level pronunciation.
Is fearr Gaeilge ḃriste ná Béarla cliste, cinnte, aċ i ḃfad níos fearr aríst í Gaeilge ḃinn ḃeo na nGaeltaċtaí.
Gaeilge Chonnacht (GC), go háraid Gaeilge Chois Fhairrge (GCF), Gaeilic Uladh (GU), Gaelainn na Mumhan (GM), agus Gaeilge an Chaighdeáin Oifigiúil (CO).

Note:

The above goes for the standard English keyboard layout (I think all of them, but I’m not sure)—if your keyboard is in a different language, you may need to use different key combinations to access the accents. For example, on my Danish keyboard, the áćúté áććéńt is a key of its own two keys to the right of the Zero key, just to the left of Backspace; while the g̀r̀àv̀è àc̀c̀èǹt̀ is the same key, but uppercase.

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Not a native speaker.

Always wait for at least three people to agree on a translation, especially if it’s for something permanent.

My translations are usually GU (Ulster Irish), unless CO (Standard Orthography) is requested.

Well, technically, mine is a Japanese keyboard, the "e" key is い, and the "_" key is ろ.

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Múinteoir Gaeilge - Irish Teacher
My "specialty" is Connemara Irish, particularly Cois Fhairrge dialect, but I can also speak Ulster and Munster Irish with native-level pronunciation.
Is fearr Gaeilge ḃriste ná Béarla cliste, cinnte, aċ i ḃfad níos fearr aríst í Gaeilge ḃinn ḃeo na nGaeltaċtaí.
Gaeilge Chonnacht (GC), go háraid Gaeilge Chois Fhairrge (GCF), Gaeilic Uladh (GU), Gaelainn na Mumhan (GM), agus Gaeilge an Chaighdeáin Oifigiúil (CO).

E is i?! How logical!

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Not a native speaker.

Always wait for at least three people to agree on a translation, especially if it’s for something permanent.

My translations are usually GU (Ulster Irish), unless CO (Standard Orthography) is requested.