1. Don't pack it away wet. If it does rain or dew collects, you'll have a towel to wipe it down. If it is still raining when you want to pack up, you have a couple choices ... wait or drag the tent into a sheltered area, and then wipe it down with your towel.
2. If you do pack it away a little damp, fold it loosely and strap it to the top of your rack. Don't roll it tightly into its bag.
3. If you do pack it away a little damp, open it out as soon as possible and let it dry. You can do that in your hostel or other indoor areas.