It's already looking much happier.
That should solve the problem.
Sounds like the soil should be fine. Mine's in a tropical potting soil with extra perlite added.
I typically water mine every few days. However, my house has terrible air circulation and gets really dry, so my plants tend to dry out pretty quick. Occasionally mine starts to wilt, telling me I waited a day too long, and it perks right back up as soon as it's watered again.
I wouldn't necessarily wait till it droops. I aim to water mine when the top ~2" of soil is aaaaalmost dry. I avoid letting it dry out completely. However, if it does droop, then definitely time for a watering.