Ouija board can be useful if used seriousely but in reality, you wouldn't need a ouija board to communicate with the other side but it makes it easier sometimes with the letters and numbers. You could also just use a deck of cards you make yourself by numbering each card and writing letters on other cards. You would put the cards all around a round table and use an empty reverse glass to have a homemade ouija board.
Many people are joking around with ouija boards and it's what makes it so fake sometimes. Some people aren't patient enough, serious enough and minded enough to be a good candidate using the ouija board. Not everyone has that sensibility with the thing and it is no used for these people to play with it.
However, any way you might try to communicate with the other side, wheither it is with a ouija board or another way, you always have to be careful because even if you expect to speak with someone specific, it doesn't mean it's this person who's going to answer to your calls. You also are in contact with the unknown somehow and you don't really know what to expect. You have to prepare yourself (90% mentally) and make sure you will be safe.
I've heard many times using a ouija board all by yourself can be dangerous but I personally don't think it could be more dangerous than in group and except if you really have blind trust in everyone participating to this conversation with you, if you are alone, you will be sure there is no joking.
Not to confuse two things thought;
-a spirit making the object move to communicate with you
or
-your own power to make things move by themselves (telekenesis)