Yo I’m pure dookie ass at caravan, would you be kind enough to give some tips?
Ok so these things? These three piles of cards?
These are your caravans. Imagine each pile represents a single pack Brahmin, and every card is a package of things to sell. As you add cards, you are adding merchandise to your caravan/Brahmin.
Those orange numbers above each caravan, reading 25-26-25? That represents the weight of the packages altogether. You can see the first one has Ace (1) + 8 + 4 + 7 + 5 which = 25 (don't worry about the queens yet). Basically, you add cards (merchandise) to have a weight value between 21 and 26. Why? Well anything below 21 isn't enough stuff to bother sending a caravan out to Reno or the Hub, and anything over 26 will overencumber your poor Brahmin.
It's basically playing Black Jack three times, while your opponent (your rival caravaneer) is doing the same. You can use face cards to sabotage them, or help yourself. Kings doubles the value (or weight) of a card; for example, those two kings up there? The first one brought that 4 to an 8, and the next king brought that 8 to a 16. Plus the 10 on top, you get 26. Jacks will just remove a card; put it on your opponents' to mess with them, or put it on one of your own if they overencumbered you.
I never bother with queens or jokers, but as far as I know queens can change suits and the order of cards (from ascending to descending, also remember that you normally need to put cards down in a certain order from low to high or vice versa, except for when cards share the same suit) and jokers... jokers can fuck with your opponents' entire deck, basically.
So how do you actually win? You just have to get your caravans to their ideal weight-value ratio (between 21 and 26) before your opponent. Easiest way to do this imo is to have a deck of 7s, 9s, 10s (7 + 9 + 10 = 26) with Jacks and Kings. If I'm low on cards, I'll throw in 6s, 5s, and 8s as well. During the Caravan Tournament mod, I got by on the default deck Ringo gave me, using 5s, 6s, 7s, 8s, 9s, 10s, Jacks and Kings.
TL;DR use cards that easily add up to 26 (7s, 9s, 10s), jacks and kings, and play an amplified version of black jack 3 times in a row quicker than the person across from you.