Can anyone with Dyslexia explain what you see when you look at words or write?

My son is 5 and has trouble writing things backwards. It started with his name and is now going to other words and numbers. I think he is dyslexic, but he is to young to test. I get frustrated when I try to teach him and I know he gets frustrated with me too. I want to try to understand how he sees things. I know what the disorder is, it's just hard for me to understand what he sees. Please help me?