Tibetan Phonetics
There is an international phonetics standard that handles any languages -- the issue is that it's hard to understand it and you need to learn basically the syntax to properly learn the sounds for the phonetic text.
Most use home-made systems for phonetics, however the THL Online Phonetics Converter tool is very handy and quick. You copy into the form Tibetan text, Unicode or Wylie, and select the output phonetics format for the phonetics output. I use the Rigpa Phonetics - English format, mostly as I help out at rigpawiki.org as well as do practice texts for the English speaking audience. There's sometimes a need to adjust the phonetics a little bit, like combining the output. There's also a debate for recitation if we should use spaces syllables (as I do) rather than whole word phonetics as the Tibetan singing system is based on syllables. But that could be adjusted to your liking. For layout purposes nowadays I use smaller capital bold letters as it's more readable in 'darker' gompa settings, but that is again a preference.
Another benefit with this tool is that you get consistency across the whole text for words rather than doing copy-editing making sure that happens.
Below is an example of the refuge and bodhichitta prayer with phonetics using this tool:
།སངས་རྒྱས་ཆོས་དང་ཚོགས་ཀྱི་མཆོག་རྣམས་ལ།
།བྱང་ཆུབ་བར་དུ་བདག་ནི་སྐྱབས་སུ་མཆི།
san gye chö dang tsok kyi chok nam la /
chang chub bar du dak ni kyab su chi
In the Buddha, Dharma and Sangha
I take refuge until I reach enlightenment.
།བདག་གིས་སྦྱིན་སོགས་བགྱིས་པའི་བསོད་ནམས་ཀྱིས།
།འགྲོ་ལ་ཕན་ཕྱིར་སངས་རྒྱས་འགྲུབ་པར་ཤོག །
dak gi jin sok gyi pé sö nam kyi /
dro la pen chir san gye drub par shok
By the merit of (this practice), generosity and so forth
May I reach Buddhahood for the benefit of all sentient beings.