With its love of warmth and humidity, this plant does well with regular misting with tepid water. Just be careful to avoid letting large water droplets stay on its hairy leaves, as this can cause rot. A fine mist is recommended.
Water your Begonia so that the soil stays moist but not overly wet. Overwatering can harm the plant, so ensure you use the watering can only when the top layers of soil dry out. And on the topic of soils, do make sure your plant sits in a well-draining potting mix.