If you are putting your sourdough start on hold for the long term, we suggest that you dehydrate it. When doing this, make sure you spread your start paper thin and dehydrate more then you think you should. Any moisture will ruin the dehydrated start. This will preserve your start indefinitely. Dehydrating your start is also a nice way to share your start with others. To revive your dehydrated start, use the following instructions:
Day 1: In a pinch bowl, soak 1 ½ teaspoons dried starter in 1 Tablespoon lukewarm purified or spring water for a few minutes to soften. Then stir in 1 Tablespoon all-purpose or bread flour, cover with plastic wrap and let sit at room temperature for 24 hours.
Day 2: To the above mix, stir in 1 Tablespoon of flour and 2 teaspoons of water and let it continue to sit covered as before for another 24 hours.
Day 3: Stir in 1 more Tablespoon of flour and just 1 teaspoon of water this time. Within the next 12 to 24 hours you will likely start to see some bubbling action of fermentation. The warmer the room, the faster the activation. Now transfer your activated starter to a small bowl and stir in 1/3 cup flour and 1/4 cup of water. Within about 12 hours you should have a lively, spongy starter. Continue to build the starter with once or twice daily feedings until you have a sufficient quantity to use for baking. You may double or triple the quantity of starter with each feeding. Feeding with approximately equal weights of flour and water (vs. equal volumes) will result in a good starter consistency.
If you are just wanting your start to rest for a week to a couple months, you can refrigerate or freeze your start. Put your start in a glass jar and cover with plastic wrap. Make one small puncture on top of the plastic and place in the fridge or the freezer. If you choose to refrigerate, it is a good idea to feed your start weekly. Then, if you are wanting to use your start, you will want to thaw/remove your start from the freezer or the fridge and let it get to room temperature.
Once your start is at room temperature, you can begin to feed and revive it for the next couple of days until you can see some bubbling action of fermentation. Again, the warmer the room, the faster the activation. Continue to build the starter with once or twice daily feedings until you have a sufficient quantity to use for baking. You may double or triple the quantity of starter with each feeding.