Raise the back of your tongue to touch the soft palate (velum). Stop the air, then release.

Americans pronounce cookie as KUU-kee (/ˈkʊki/). Stress falls on the first syllable — keep everything else short and quick. You'll hear it in sentences like "Put sugar in the cookie".
Record yourself saying "cookie" and play it back. The mic stays on your device — nothing's uploaded.
2 syllables, 4 sounds. Tap a syllable to jump to its row, then explore each sound's mouth shape and how it's made.
The textbook way isn't wrong — it's just not how anyone actually says it.
Stress falls on the first syllable, not the others. Stretch KUU — keep everything else short and quick.