I use them personally and in my healing practice. They work best when you find a deck of cards that you really like. There are a number of websites that offer choices. I just checked out Amazon and there are 926 varieties of cards. In fact, I found another one that I would like!
Once you receive the cards, it is helpful to make a daily practice of working with them. You close your eyes, center yourself and think of an open ended question. A suggestion is " what do the fairies, angels, or animals want me to know today". At this point, you move one hand over the card spread and pick the one that your hand is guided to.
Have fun. Please take care and you will see the fairies in the tree.