Guidelines and instructions can be found and downloaded here: Protected content
Sirens in Tel Aviv give you about 90 seconds to run for cover: Protected content
Map of interactive safe spaces in Israel (bomb shelters, etc): Protected content
Please now that for every rocket fired at the centre (e.g. Tel Aviv and Jerusalem), two Iron Dome anti-missiles are fired, increasing the chance of the rocket being intercepted. The Iron Dome intercepts the rockets ideally over uninhabited area.
The current warning is that everyone living 40km away from Gaza should stay close to shelters and not gather in large groups outside. No special warning have been given for the rest of Israel.
Tel Aviv and area has now opened the public shelters.