Yucca elephantipes is fairly low maintenance and requires watering once the soil becomes somewhat dry. It's not especially drought tolerant like nearly all the others in the genus. Plenty of sun or bright light is essential for good growth. Light general purpose fertilizer periodically will also aid it the plants overall health. Cheers, LPN.
What LPN said. Once your plant is happy and begins to mature, you can strip off the drooping, yellowed leaves without harming it.