Hot tubs are the best place for relaxation. If you're the type who gets too nervous on dates and often does things all wrong, then this could be an ideal date for you. People who are relaxed often drop their inhibitions and act naturally.
If you have a soft tub at home, you can ask your partner to soak in with you. Perhaps you can even offer a massage and get intimate. You can do it under the moonlight amidst the house garden, or in the patio. Outdoors or indoors, all that is really needed is the right mood.
Don't get all clumsy, and spoil everything at the last minute. It's better if you can set up the soft tub and heat up the water at the right temperature before your date arrives. If you don't have the chance to do so, at least prepare some snacks and drinks to keep your date occupied while you're setting it up.
Don't forget the bath gel, massage oils, and towels. Every detail adds to the success of a romantic date. Who knows, you can even use this chance to propose!