Wash hands thoroughly
Use clean, sterile containers and utensils
For 0.9% saline (normal saline):
Measure 9 g of non-iodized salt (or kosher salt) per 1 liter of water
Add salt to water and stir until fully dissolved
For smaller amounts (0.9% saline):
1 cup (240 mL) water + 0.22 g salt
1/2 cup (120 mL) water + 0.11 g salt
1/4 cup (60 mL) water + 0.055 g salt
Use only water that is safe to drink:
Boil water for 1–3 minutes, then cool to room temperature
Or use sterile water
If using for wound cleaning, contact lenses, or injection preparation:
Do not use homemade solution
Use commercially prepared sterile saline
Label the container with the date/time made
Store in a clean, covered container
Refrigerate and use within 24 hours
Discard if it becomes cloudy, develops particles, or smells unusual