Hi and Welcome new piggies to be 
Puppy pads- some pigs will chew them and they have plastic sealing the edges of the ones I bought last. My ladies are a bit vandal~ey , the boars never touched them.
My pigs have just gone out today into their Pighouse for 24 hour living (they were indoors at night time from Guy Fawkes til now).
I used those wooden cat litter pellets ( they are recommended for small furries) they absorb well and crumble into a bran like texture. I just put a few layers of newspaper on top then the hay. Roll it up, take out any manky patches with a scoop, and remake with fresh paper.
I buy it from The Range , big bag lasts months. (Some wood litter stinks
)
Megazorb (an equine bedding) is popular, it's light and absorbant but dust free. I bought some cardboard equine bedding (it's in small squares, I bought three huge bags from an equine supplies shop) .
We've tried everything - fleece,newspaper,towels,shredded paper, various equine beddings.
the wood pellets/newspaper/hay cookies for indoors worked well (less messy than loose hay)
outdoors- rubber carboot liners, cardboard, newspaper, equine bedding on the floor and deep hay in their hay box.
Boxes (two doors) , tunnels, Primark bags (without handles) - keep them busy .