I have used them, and for me they are very accurate.
I have several decks, but I use only one, and for me that is the big secret. You have to sometimes go through several different decks before you find one that really speaks to you with its imagery.
If you just have a regular Rider Waite deck (which lots of people start with) I would start by just memorizing the suits, cups, pentacles, wands, swords, and what those refer to. Then I would go on the numbers, and what they represent. Then I would memorize the Major Arcana. Then I would start with simple three card pulls so that I had less to integrate.
Then I would go for a new deck if the imagery on the deck I had didnt really "add" anything to the normal card meanings in terms of subtle clues and nuances.
I hope that was helpful and not too "duh" obvious.



. You're right I am starting with the original Waite deck (that's all I was able to find at the moment) but eventually
I'd like to get one of those fancier ones, there's so many nice ones out here. Starting off with memorizing the cards is a good idea and I'm also a
terrible shuffler
. I guess the thing to do is to just keep practicing.
(my apologies if someone mentioned that already)