I quote the following instructions from the RationalWiki.
You will need two decks of 54 standard playing cards with identical backs and different faces; in the US, a Bicycle Standard or Jumbo Index deck and a Bicycle Lo-Vision four-color deck will do. (This example is based on that combination.)[4]
Take the cards from the standard deck minus one joker (the other joker will be the Fool). Mix in the A->10 cards from the clubs (blue) and diamonds (green) from the Lo-Vision deck along with the Ace of Spades (black) and the jacks from all four suits; the clubs will be trumps 1-10, the diamonds (because a diamond's worth more than a stick) will be trumps 11-20, the big-index jacks will act as cavaliers,[5] and the ace of spades will be trump 21. You are now ready to play any tarot game using a standard 78-card deck, and you won't have to frustrate yourself with the artsy-fartsy markings on a cartomancy deck or pay obscene shipping charges to import a playing deck from France or Italy
------------------
4- Total cost approx. US$ 7, depending on supplier
5- You could also use three decks with three different index sizes, making the cavalier-jacks the middle-size index cards, but it's probably a waste of money to tear apart a third deck just for the jacks
http://rationalwiki.org/wiki/Tarot#cite_ref-1
To sum it up, Here is a little table which breaks down the deck's structure
( the Letters in colour represent the cards of the Lo- vision deck, the "C" stands for a knight )
Tarot
trump |
Fool
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
Replacement
|
Joker
|
A
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
Tarot
trump |
11
|
12
|
13
|
14
|
15
|
16
|
17
|
18
|
19
|
20
|
21
|
Replacement
|
A
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
A
|
Plain Suits (Tarot)
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
J
|
C
|
Q
|
K
|
Replacement
|
A
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
J
Normal |
J
(Big
in-dex)
|
Q
|
K
|
However, In this blogger's opinion, isn't part of the joy in playing at tarot the beauty of the cards?
[Edited 23rd Dec. 2018, to cure formatting error]