That's a complicated question. There's no best way, it just depends on your personal preference, the ducks' needs, your budget, and so on.
What type of housing you need depends a lot on the predators in your area. You can only let them free-range if there is little chance of them straying or being eaten by predators. Many people have a coop attached to a run or pen, which has ample space for playing, bathing, and foraging. The coop is virtually predator-proof, and the run or pen has a fence.
If there aren't many predators, and you're not planning to hatch, you could get by without a coop – just a large fenced pen and plenty of shade.
How many ducks do you want? Ducks need 5 square feet of space inside and I think 10 square feet outside, (assuming they will be inside for the night and outside for the day) but bigger is always better, especially for the outside area.
The breed – Pekins are good meat ducks, eat a lot, and also lay a decent amount (125-225 eggs a year). There are plenty of other options for breeds, too. There are some breeds that lay over 300 eggs year, but aren't good for meat, and there are some dual-purpose breeds that work for both purposes (Appleyard, Orpington, Saxony, etc.)
If you could give me a better idea of the predators and your needs, I can give you more tips.
