Ouija boards/Talking noards aren't as dangerous as any other methods of contacting spirits, it's in the way you use it. It is simply a tool, and does nothing until you touch or pick it up. You just have to know what you're doing, cast the right protections, ask the right questions, avoid asking for proof or the spirit to come out in any possible way, and you should be fine. Be sure that you cleanse the room that you will be working in before hand, keep your mind on the task at hand, and never use it alone. It's safer to have one or two other people with you. Call upon your personal deity(s) for protection if necessary. Remember, some spirits lie, so double check, and be skeptical.
If you would like a protective prayer to use before your ouiji board session, then I would suggest using this one. (I didn't write this prayer, but I do use it in every ouiji session.) :
[God/Goddess' Name] , I invite you to our space to watch over our ouija board session and keep us safe throughout. Give us comfort in your presence and the knowledge that we are watched over. Give us the wisdom to discern the spirits from tricks of our minds. And give us the strength to banish if we need to. We ask for protection, clarity of mind, and comfort.