If you're having a conversation with someone you can point to the word and ask how to pronounce it. I agree with Saul, a lot of time if you google "Pronounce ______" with your word in the blank spot, there will typically be a youtube video or a clip of sound for you to hear how to properly pronounce the word

The best thing when you don't know how to pronounce a person's name or the name of a place is to try to sound it out, but if it is too hard, you may look the word up in a dictionary online and they usually have recordings of how the word is pronounced.