1. Put ingedients into a preserving bottle and cover softly with plastic wrap

2. Microwave on 600W for 30seconds. (15seconds on 1200W)

3. Take out the bottle, stir until the salt melt and screw top. Last for 2 weeks at normal temperature.

For how long you should cook with your microwave oven, see Cooking Time vs Wattage Conversion.
For more tips of using Microwave Oven, see Sachiko's Guideline to Microwave Cooking.