The other suggestion is to put your slip cover back on the furniture and spray it (lightly, don't soak) with Downy Wrinkle Release and smooth it out with your hands and let it dry. I use this on my DH's shirts and it works fairly well. I know there's a home-made version of this product but this is the one I use and haven't ironed anything in years.

We had a conversation about this a while back. I can't link it for you on my tablet but it is titled as below if you want to look for it,

Am I the last one to know about wool dryer balls?

I dry with two tennis balls and think it is helpful.

I made some felted wool dryer balls a few years ago. I think they help.

Along with the dryer balls (commercial or homemade - which have been shown to help prevent wrinkles and aid in drying faster), you might get additional help with a spray bottle of Wrinkle Releaser (Dollar General) to spray and smooth out any remaining wrinkles with your hands after you put the slipcovers back on. If you are concerned with chemicals from the Wrinkle Releaser spray, you can also remove wrinkles with my hand-held steamer. Small Fabric Steamers are fairly inexpensive ($20 and up).

Grainlady,

I will look at the spray and check out the ingredients. I try to be careful what I spray because I have some small birds.

I actually have a device called a 'Homedics Perfect Steam'. However, it has sat in a closet for a couple of years, and I am apprehensive that maybe it might have rust, and I don't have a clue as to how to clean it.

All 3 slipcovers are washed, dried with dryer balls, and put on. There is a little wrinkling in the front panel near the floor but everything else is better than I expected. Of course, I didn't do a comparison test not using balls so I can't attribute the success all to them.

I made some wool dryer balls and don't see any difference. I have also used the regular ones you can buy and its the same, no difference. It may help fluff, or it may help cut dryer time but I'm not convinced.

I was glad to get away from dryer sheets and the balls have been adequate replacements. I would dry the slipcover on low setting and fit them on furniture asap for least wrinkles.

eta: looks like that is what you did.

I do use nubby dryer balls for drying items of heavier fabric. But one time I forgot to remove them before tossing something more delicate inside, and the abrasive contact caused pilling.

Found the steamer directions online, cleaned with vinegar, and steamed the slipcover part with wrinkles. Only partially successful but on the whole it is acceptable. They don't look like my fitted set, but putting them on and taking them off is easy so I'm willing to settle for not perfect, because I want white slipcovers (at least until the fall) and I want dogs in the living room.

Tennis balls are not a great idea, especially if you use the highest heat setting. The rubber smell gets in the clothes and is obnoxious. Dryer balls can be had cheap enough. Dollar Tree had them for $1/pair. There's even some that claim to be more anti-static but I haven't made the plunge. I think Grainlady tried them IIRC and had positive things to say about them. I have an extra large dryer so I use 6 of them in there and it makes quite a difference. I don't have any documented proof but have noticed a difference when I haven't had them in there. Towels especially.

You'll get less wrinkling if you don't overload the dryer and if you don't overdry things. Static comes from overdrying clothes too so you don't need dryer sheets or anti-static spray and you'll spend less on your drying costs if you dry them properly in the first place.

It will also help to remove from the dryer while still warm and put them on. That should limit wrinkling too.

oops, misunderstood the title!

I was gonna say "cornstarch".