Bunches of fresh curry leaves in Picture 1.

Separate the leaves and sprig, discard the sprig.

Soak the leaves in water for 15 minutes and wash twice or thrice as long as you see dirt in water.

Drain the water, dry over cotton cloth for 30 minutes to absorb excess moisture.

Make a bundle and press gently with the same cotton cloth to remove excess moisture.

Pat dry over mat or cloth under direct sunlight for a day, once leaves turn pale and shrunk you can transfer it to shaded area.

Or you can dry in hot sunlight till they turn crisp.

Also you can dry under shade (takes long time) or use a food dehydrator, air-drying, oven drying and microwave drying methods for quick drying.

When you touch you can feel its crispness also when you break in between fingers it makes sound, that's the right indication.

Once you reach that stage (Picture 2) you can powder it.

If not you can warm in the oven at 200 F for 3- 5 minutes at regular interval and don't burn it (can refer my Ajwain Leaves / Oregano).

Once done using Mixie / Food Processor powder them (Pic 3) and sift using the tiny hole strainer to get fine powder out from it (Pic 4).

The coarse curry leaves (Pic 4, I have used it in the chutney recipe) can be used directly in sambar / rasam or in chutneys.

Or it can be powdered again, if necessary you can warm the coarse curry leaves and make it to a fine powder.

Once done with it, you can add optional salt for longer shelf life and do store in air tight container at room temperature.

I have enough quantity at Room temperature and remaining stored in the refrigerator for later use.