if you want to smother weeds and seeds put the cardboard over whatever else you may put down. cardboard then weed barrier then wood chips makes a very effective weed smothering. overlap a few layers of cardboard by enough distance to make sure no light gets through the cracks.
this method we use to go over lawn areas and nothing comes back through that.
for areas where i may want to cultivate again in a few years time after the weeds are suppressed i will use cardboard layers and any mulch to cover that i can scrape back to replace the cardboard as it does get wet enough here that the cardboard will mostly be decayed/worm eaten by the end of the first year. so it needs to be replaced, or retopped up again to keep the weeds smothered the second year. normally after that point if the area is not disturbed it will not sprout many weeds after that, but there are always some weeds that will blow in on the wind or come with the rains or animals move the seeds around.
for a garden bed you expect to use next spring mulch it with whatever amendments you want to use and then put the cardboard over that until next spring, weigh it down so it won't get moved by the winds. you'll need more than one layer (to overlap the seams). i would not put anything else on top since you plan on removing the cardboard next spring. if you want to put tarps over that you can do that too and put your weight on the tarps. that should smother quite a bit until spring.
whatever is left of the cardboard in the spring you can bury or use under pathways/areas you plan on walking between the rows of plants. there will likely be some mouse nests and perhaps snakes/etc under there, that's ok. they'll move on when you change things around.
cardboard is not a permanent pathway or barrier material, that is why it works well IMO. it does the job and then goes away as the worms and wood lice, etc eat it.
for a formal garden bed you do want a good edge down in the ground to keep intruding roots from grasses and other weeds to have an easy pathway into the garden bed. at least three feet of pathway inside the edge and the second edge to keep any weeds in the formal garden bed from getting out under the pathway. we have crushed rinsed limestone used as pathway mulch around a lot of areas here. it works ok, but once it gets any dirt in it or any garden debris then it will eventually start sprouting weeds too and it will need to be taken up and cleaned to get it back to mulch only. after 20-something years here i have places that rarely sprout any weeds at all because they get no real action at all and other areas have become nearly constant problems of one sort or another and need some work. with as much area as we have i've removed some pathways that were useless (and that has saved me some time already this past garden season
) and it also gave me more space to plant garden vegetables (more beans !
)...
i much prefer wood chips as pathway materials once i have a good weed barrier down and my edges in place. that way when the wood chips break down they can be removed or topped off with new wood chips and the humus can be used in the gardens. more than that though i much prefer no pathways at all and having larger spaces to manage as i can rearrange how i plant a garden without having to work around the pathways and also every edge in a garden is work to keep up. the fewer edges the easier things are. just one good border around the larger garden and as part of that border make it a good fence with the wire mesh under the pathway to keep the animals from digging under the fence. saves a lot of later troubles to have a good fence in place.
