Caravan is easy, once you get the hang of it. Sorry if this explanation is quite unclear, but I'll try my best

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Basically the idea is to get your three lines of cards (your "Caravans") to a value of 22, 23, 24, 25 or 26. You win if you have all three at that value or if you have 2 and your opponent can't match them of get the magic three Caravans in their next turn.
You can't win, however, if one of your opponents Caravans is at the same value as yours e.g. if you have three Caravans at 23, 24 and 25 but you opponent has 12, 13 and 25, you have to alter their 25 Caravan by using Jacks or Jokers or alter yours in the same way, or use and Ace to make it a 26 in order to win that hand.
You have to put Caravans in ascending or descending order e.g 2, 3, 4, 5/10, 9, 8, 7. There can be as big a leap as possible between the cards e.g. 2 can be put on a 10, but your next card then needs to be an Ace or face card. Queens change the direction of a Caravan, however, e.g. If you put a 2 on a 10, then a Queen on the 2, you could put any card on it rather than an Ace.
In your deck you should ideally have no more than 45 cards - I have 42. You should also a good mix of cards too, in mine I have:
Aces - 4
2s - 3
3s - 3
4s - 3
5s - 2
6s - 2
7s - 3
8s - 3
9s - 3
10s - 4
Jacks - 3
Queens - 3
Kings - 4
Jokers - 2
Jacks get rid of the card you place it on, so try to put it on your opponents highest valued cards (8s, 9s, 10s). If you put a Jack on a card that has a King attached to it, it gets rid of both the Value card and the King. Can also be used on your Caravans.
Queens change the direction of your caravan e.g if you have a caravan going 10, 6 and have an 8 in your hand, you can place the queen on the 6 then place 8 next turn to make a caravan of 24.
Kings double the value of a card e.g. Putting a King on a 10 makes it 20.
Jokers get rid of all cards the same value of the one you put it on e.g. if you have one 8 and your opponent has three 8s, you can put a Joker on your 8 getting rid of the three 8s your opponent has.
When placing your three lines try to put 8s, 9s, 10s or Aces as your starting cards so that you can use your middle value cards to extend the Caravan.
Try to put any Kings on 8s, 9s or 10s to increase the usefulness and lowering the number of turns needed to make a Caravan.
I only use Jacks on Opponents cards and when they are close to making a Caravan.