To be brief, xylitol is a naturally-occurring plant-based sugar substitute that apparently has all sorts of anti-bacterial as well as anti-fungal properties. Given these properties, daily xylitol gum chewing or xylitol nasal spray use has been shown to help prevent recurrent acute ear infections and sinus infections... safe for use even in infants.
When used as part of nasal flushes to the nose, it seems to work even better than traditional saline flushes to the nose (read more about this here).
So, I have provided below a few different recipes to make xylitol nasal flushes at home. One may be more comfortable than the other, but it is user dependent. Obviously, convenience will play a role as well.
Just as an FYI, you can also purchase pre-packaged packets that contain xylitol for the ultimate convenience. Just open one packet and mix it in with water inside your nasal flush kit of choice (Nasopure, Neti Pot, Neilmed, etc)
Recipe #1 (Complex):
1 cup of water (8 ounces)
1/4 tsp salt
1/2 tsp of xylitol crystals
1/4 tsp baking soda
4 drops of grapefruit seed extract