What one needs to understand regarding Tarot is, the more they are used for other purposes besides divination, and the more people touch them besides yourself, the worse they are tuned to your soul and to the act of divination itself.
For the best result, one needs a Tarot deck with spiritual imagery that does not have any xian connotations and is free from enemy imagery and corruption, then the deck should only ever be used and touched by you. Nobody else should have their hands on it ever under the best circumstances.
After purchasing, clean the entire deck spiritually to remove any external influence from it, then breathe energy into it to empower it and program the deck to be attuned to your soul and your will, and program it to always divine accurately the truthful information you ask for.
Then put it under your pillow and sleep with it for a few days, this helps to further tune the deck to your energy.
Perhaps this sounds a little unusual, but it is how one attunes props to your own energy and soul.
When you do a reading with a tarot deck, make sure your own energy is raised first, then do the reading with a clear mind, tuning into the divination as deep as you can and let the cards be the medium for the information, knowledge and potential you tap into to express itself and lay itself bare to you. Then you interpret the meanings of the cards drawn according to the principles of the Tarot (Good decks will have a manual that explains how to interpret the cards properly).
Again, for the best results, only do one single comprehensive reading at a time, do not try to read multiple people in short order, or ask many different questions in short order, as the energy from one divination will linger not only on your senses, but especially on the cards, affecting the accuracy of readings made right after.
One hour or so is a good time frame to wait, and limiting the number of readings to 4 a day is generally a good rule of thumb for maximum accuracy and effectiveness.
I do not know how having multiple decks would behave, but I assume as long as you clean the area properly and close of the previous reading well while putting one deck away to "let it rest", would allow one to use another deck to do another reading some minutes after without too much energetic pollution to affect the accuracy of the reading, so long one is proficient at handling energies.
Using playing cards to do any sort of serious divination is not really effective, as the cards simply do not work the same, not to mention, there is no major arcana equivalent at all in a set of normal playing cards, and the symbols of the Rods, Clubs, Cups and Swords have spiritual meaning which is lost when the symbolism is changed.
The subconscious mind ties into the spiritual meanings behind the cards when using a proper Tarot deck, which is why it is important to use one with art that doesn't have any abrahamic influenced artwork on the cards for the greatest effectiveness.
If all this is adhered to, Tarot cards can be one of the best props to use to assist you in divination, if not the best. It is a lot more accurate and easy to use than say a pendulum which takes great skill to interpret properly and has a high chance for misreadings or false readings.
If you want to do divination, learn how to maintain the props spiritually and do the proper motions to charge the props and tune them to your soul, clean them very well and prevent anything from polluting them. Again, I cannot stress enough to not let other people place their hands on your cards, it will pollute them with external energies and mess with the cards ability to tune into the divinitory energies you want to interpret through them.
Keep those grubby hands away from your spiritual tools. Only people who are very skilled in closing of their energies can carefully handle your spiritual items without messing with them and causing you to have to clean them profusely, the chance you'll know someone like that is basically nill.
Even I would refuse to touch the personal Tarot deck of a fellow SS to prevent interfering with it.
Hail Satan!
