I've taken plenty of hard falls while out on the slopes and still wear wrist guards - they're not just for beginners, and honestly the peace of mind alone is worth it. The key technique is learning to fall on your forearms and butt rather than catching yourself with outstretched hands; when you feel yourself going down, try to roll with it and distribute the impact across your whole body instead of jamming it all into your wrists.
Beyond guards, strengthening your wrists and forearms with basic exercises before season helps a lot, and getting proper lessons on technique (especially edge control) reduces falls in the first place. A lot of people who get nervous after a bad fall actually benefit from a refresher lesson - it builds back your confidence and catches bad habits before they stick.