GMC 1994 Sonoma Owner's Manual page 279

Using Foam-Type Cleaner on Fabric
Vacuum and brush the area to remove any loose dirt.
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Always clean a whole trim panel or section. Mask surrounding trim
along stitch or welt lines.
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Mix Multi-Purpose Powdered Cleaner following the directions on the
container label.
Use suds only and apply with a clean sponge.
Don't saturate the material.
Don't rub it roughly.
As
soon as you've cleaned the section, use a sponge to remove the
suds.
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Rinse the section with a clean, wet sponge.
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Wipe off what's left with a slightly damp paper towel or cloth.
Then dry it immediately with a blow dryer or a heat lamp.
NOTICE:
Be careful with a hair dryer or heat lamp. You could scorch the
fabric.
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Wipe with a clean cloth.
Using Solvent-Type Cleaner on Fabric
First, see if you have to use solvent-type cleaner at all. Some spots and
stains will clean off better with just water and mild soap.
If you need to use a solvent:
Gently scrape excess soil from the trim material with a clean,
dull
knife
or scraper. Use very little cleaner, light pressure and clean cloths
(preferably cheesecloth). Cleaning should start at the outside of the
stain, "feathering" toward the center. Keep changing to a clean section
of
the cloth.
When you clean a stain from fabric, immediately dry the area with an
air hose, hair dryer, or heat lamp to help prevent a cleaning ring. (See
the previous NOTICE.)