Installing circuit for tanning bed 220v 30 amp
For a 240V/30A circuit, 10 AWG copper is indeed correct (it's the same stuff you'd pull for a dryer hookup).  You'll want to use 10/3 NM (instead of 10/2) so that you can have the option of converting the circuit to 120/240V 30A or installing a subpanel at a later date.