Keeping lawn furniture and other items in good shape when they are usually left outside can be both simple and complicated. It's simple in that the steps you take aren't that unusual, but it can be complicated because there are so many things that could ruin the items you store outside. One step you can take that will protect these items from more than one of those things is to cover items with a fitted cover that is protective against UV rays and that is so tough that nothing will be able to claw its way through the cover. What you have to cover falls into three general categories.
Anything Outside That Doesn't See a Lot of Use or Is Seasonal
The first category, and the one you're likely already looking for a cover for, contains items that don't see a lot of use or that are used seasonally. Perhaps it's the ping pong table that you use when your family visits for the holidays but that doesn't see much use the rest of the year. The cover can keep the dirt and dust off, so the table remains clean enough to use. The grill that doesn't get used during the winter months is another example. Even if the grill has a metal cover that came with the model, you want something that you can essentially wrap around the entire grill in the months it's not used.
Anything That's Under a Tree
Have you just moved into a new house and haven't seen how the trees in the yard change from season to season? Assume that at some point, they will have a lot of leaves that will fall or be blown off by a strong wind. Anything under or near those trees should have a cover for when no one's using the items. For example, if you have patio furniture near the trees in your yard, you may want to keep that furniture covered starting in late summer when the leaves start to fall. You can uncover everything when you want to use it, and then re-cover everything when you're done. The alternative is brushing a bunch of leaves and seed pods out from under and between the cushions. The cover is better.
Anything That's Not Stored Under an Awning
Anything that sits out in the yard, with nothing to cover it, should get a cover. Huge items like a swingset might not need one, but small playhouses, for example, can be easily covered. (Only do this if the kids using it are old enough to know not to play around with the cover.) The cover protects the items from rain and bright sunlight when they aren't in use.
If it sounds like your yard is going to look like an attic full of furniture under dustcloths, don't worry. Not everything will have to be covered (furniture protected by an awning that is used frequently, for example, doesn't need a cover most of the time), and covers come in colors that blend in nicely with the rest of your yard. To explore options for your own yard, talk to a cover supplier near you.