Choosing your first deck can be a lot of fun, but for others can be an exhausting process of buying multiple decks only to find they do not work for you. You should choose a deck that makes you feel happy inside, feels likes connects with your religious beliefs or hobbies and should inspire you in your daily life. If a certain deck calls out to you, go with that one! They should never be boring or mundane as you will be spending a lot of time with your cards.
Decks come in many different forms. The most common card decks consist of 78 cards with 22 Major cards and 56 Minor cards divided into 4 suits. Most decks are built on this model. You should probably stick with a standard deck to start with until you learn the basics of card reading.
Many decks are oriented around a theme. This is especially true of modern decks. Although the modern decks are themed, they are also set up to reflect the 4 suits. when you choose a deck that has a theme, make sure it is a theme you use regularly in your daily life, so you do not get bored.
The Rider-Waite is the one of the most used decks and the deck most people begin with when learning. There are plenty of places on the internet to purchase your cards from, but generally I advise to buy the cards in person, as sometimes when you purchase online you cannot return and end up with hundreds of cards sitting around in your home unused. Buying in person is a better way to know which deck is for you. Sometimes you can pick up multiple packs from the same deck and get a completely different energy force from them, go for the one that makes your awareness enhance and warm inside or your hands warm up to instantly.
Regular playing cards can be used, but it can be hard to learn all the cards off by memory, so people commonly use cards that have a wording on them to remind the reader of what the card means and pictures help you memorize these.
Holiday themed cards are fun, but they are not the best choice for more in-depth reading and more serious work.