The Tarot deck is a very personal thing. You should choose a deck you like.
You will get better results if you like the feel or the artwork. One of the secrets is you should always use the same deck. According to a book I read many years ago, the cards pick up your energies and vibrations in addition to energies and vibrations of the people you will read for.
The more vibrations the cards absorb, the more powerful and accurate they become. Actually, they don't become more powerful - you do. You're ability to sense and tune into the vibrations is what determines the accuracy of your reading. The longer you have the same cards, the more in tune you will be with them, and your accuracy will increase dramatically because of this.

It is important that you allow the person you are reading for to handle the cards so they can pick up the person's vibrations.

Usually every Tarot deck comes with some simple instructions and a brief definition of what each card means, both in its normal and reversed state. These definitions are just a guideline, and are not written in stone. Rely upon your inner feelings to sense what the card is trying to tell you. You can look at the booklet to see what the usual definition is, but if you feel the card means something other than the written definition, go with what you feel. One of the suggestions this book made was to get to know your cards by placing one under your pillow and sleeping on it. Whatever you dream about is what the card will usually mean during a reading. Going through 78 cards this way can take forever, but you'd be surprised at some of the differences such a technique can bring forth. If you try this, go with the Major Arcana cards first, since I always consider them the most powerful.

Above all, don't second-guess the cards. If you feel they are trying to say something, don't surpress it because what they are telling you doesn't conform to the prescribed definition.

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