Tulip bulbs are hardy and are typically planted in the fall so they can take root during the winter and bloom in the spring. You can actually plant tulip bulbs anytime, but if you are waiting for their ideal planting time, then you must properly store them so they don't rot in the meantime.
Lay the tulip bulbs out on newspaper to dry. If they are dirty with soil, wash them off first. Drying should only take a few hours. Do not dry in the sun.
Dust the tulip bulbs with sulfur powder which will help prevent the bulbs from rotting in storage.
Bury the tulips in an open container with dry peat moss, sand or vermiculite. Do not moisten the soil first.
Place the container in a dry location that is between 40 to 50 degrees F. A garage, attic or crawl space may be ideal locations. However, since it is probably summer time and you are waiting for fall to arrive before planting your tulip bulbs, all these places may be too warm. Alternatively, place the bulbs in a refrigerator on a shelf. Remove all your fruits or move them to the crisper since some fruits let off ethylene gases that can sterilize the bulbs and they won't bloom.