Raise the back of your tongue to touch the soft palate. Add vocal cord vibration, then release.

Americans pronounce gradual as GRA-joo-uhl (/ˈgrædʒuəl/). The L in "gradual" is a dark L — the back of the tongue rises toward the soft palate, adding a small "uh" quality before the L. This is called the Dark L vs Light L, the kind of sound shift that makes everyday speech feel effortless. It comes out as GRA·joo·uhl. Stress falls on the first syllable — keep everything else short and quick. You'll hear it in sentences like "Personally, I would prefer a more gradual approach to change".
Record yourself saying "gradual" and play it back. The mic stays on your device — nothing's uploaded.
3 syllables, 7 sounds. Tap a syllable to jump to its row, then explore each sound's mouth shape and how it's made.
Raise the back of your tongue to touch the soft palate. Add vocal cord vibration, then release.

Curl or bunch your tongue without letting the tip touch the roof of your mouth. Brace the sides of your tongue against your upper back teeth, and round your lips slightly.
Drop the jaw noticeably. Keep the body of the tongue low and forward, and don't let the back of the tongue raise toward the soft palate. Pull the lip corners back slightly, almost a starting smile.

The textbook way isn't wrong — it's just not how anyone actually says it.
The L in "gradual" is a dark L — the back of the tongue rises toward the soft palate, adding a small "uh" quality before the L. Dark L adds a small schwa-like "uh" before the L. The back of the tongue lifts toward the soft palate.
Stress falls on the first syllable, not the others. Stretch GRA — keep everything else short and quick.
Don't pronounce the second syllable too fully. The unstressed syllable reduces to a schwa — the lazy "uh" sound — in casual speech.