Roll percentage dice a few times for short words, roll more for longer words. Each roll is a distinct sound. Just roll until the DM says to stop. These results form a pronunciation key for the word, it can be spelled however you wish. You may need to mix up the results a bit or add some vowel sounds to render a word pronounceable.
[1- 44] - Use the Base 44 Chart
[45 - 100] - Make a unique chart for each language using the Blank Language Template. Just put the name of the language at the top, and pick the ten most frequently used sounds for each language.
|Blank Language Template|
Below is the language chart I use to make names for human commoners, bandits, barbarians, tribesmen, pirates and more. The percentages used here are similar to those heard in American English, but far less precise. It's handy to roll up some names and words before the game, just in case you need the name of someone's nephew or whatever. Rolling up words like this can be time consuming, but in moderation it can be fun let the players roll one up at the table.