Here's how to convert it:

1. Move the decimal point to the right until you have a number between 1 and 10. In this case, we move it five places to the right, giving us 3.92.

2. Count the number of places you moved the decimal point. Since we moved it five places to the right, the exponent is -5.

3. Include the negative sign because the original number is negative.

Therefore, -0.0000392 in scientific notation is -3.92 x 10^-5.