Once you have the project smooth enough to finish (by sanding,
planing, scraping, or whatever), wipe it down with a dry microfiber
cloth to remove dust from the surface. Then apply your first coat of
wipe-on poly. Wait for it to dry, then sand the surface with 400-grit
sandpaper. Wipe again with the microfiber cloth, and apply another
coat. Repeat. Repeat again, using 600-grit this time. Repeat once
more, using either 600- or 800-grit. When dry, sand with 1000-grit or
finer (available at nearly any auto parts store), and wipe with the
microfiber cloth. You're done, and the surface will feel like glass.

Thanks Doug. I assume that T-shirt material qualify as "microfiber"
cloth. I've got a tack rag too. I was going to rub with a rag with
denatured alcohol to clean out the pores of the wood before the first
coat.

I use my shop vac with a brush attachment. This pulls dust out of the
pores, lets me clean tight areas like the inside corners of cabinets, and
cleans out recesses like dado's or shelf pin holes. For me the shop vac is
faster, easier, and more thorough than trying to wipe the dust off.

No matter what you do, the first coat of poly will always have little dust
nibs and raised wood fibers. Do a light sanding with 320 grit and clean
with the shop vac again between coats. Works great for me even in a dusty
garage workshop.

Anthony