There is no fool-proof method for cleaning vintage fabric, whether it's clothing or textiles. I can only share what works for me.
A definite 'Not To Do' is putting anything in the washing machine!
No matter how much you're tempted....just forget that handy gadget even exists. Even hand laundering can make you weep when you immerse a garment in water without checking for colorfastness. I use a dampened Q-tip for this. The most notorious shades for color bleeding are red, navy and black, but the more synthetic the fiber, such as polyester, the safer you are.
Over the years I've found that a lot of dresses that say 'Dry Clean Only' can be gently soaked in cool water with Woolite. It's just a matter of common sense, really. Most vintage synthetic chiffon dresses I've had over the years have hand soaked beautifully.
One cleaning agent I simply can't live without is Sodium Carbonate, which is a washing soda that isn't toxic like laundry detergents and is less harmful to the environment.
This can be found at Dollar General or Dollar Tree for less the your store name brands. Basically it's the cheaper version of Clorox II. Pretty much the same ingredients.
This chiffon beaded evening dress had what appeared to be a huge stain down the front of the dress. The previous owner probably had a close encounter with an entire cup of coffee. It had even gone inside some of the beads. And the tag? Dry clean only, of course!
So, into the tub she went in a bath of cold water with a quarter cup of Sodium Perborate/Carbonate for a couple of hours and she was good as new. A plastic kitty litter tub is the perfect size for most stain removal jobs. I then gently lifted the gown out and put it in a tub of clean water to soak to remove the cleaning agent. I do this several times to make sure all residue is gone, then hang the dress up in the shower and let it drip dry naturally. This helps reduce any wrinkling.
So don't toss that favorite party dress in the Goodwill bin.
With a little time and TLC she'll live to party on another day♥
Other small stains, I've found respond very well to Shout. I squirt a little on the area and gently massage it in. After about an hour, I rinse it out in the sink basin....bloth it with a towel and hang it up to dry.
Now bear in mind...this is what works well for me.
I've used these two products very successfully for over fifteen years. If your new vintage garment has no odor and any stain you find is in an inconspicuous place, you may want to refrain from cleaning it. These lovely fashions from the past are for you to love and enjoy and you may even add a stain or two yourself.
Vintage clothing has traveled through time and with a little love and care, will be around for many decades more for others to enjoy.