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

Americans pronounce cashier as ka-SHEER (/kæˈʃɪr/). Stress falls on the second syllable — keep everything else short and quick. You'll hear it in sentences like "The cashier scanned all the items and bagged them neatly".
Record yourself saying "cashier" 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 second syllable, not the others. Stretch SHEER — keep everything else short and quick.
Americans use a relaxed retroflex R — the tongue curls back rather than rolling. The R is one continuous sound with the vowel before it, not two separate sounds.