Whenever your ammonia or nitrite read 1.0 or above, do a 50% water change to lower the levels to a less toxic range. For a while that will mean frequent changes, but it may preserve your fish's lives. The ammonia will peak, then as it lowers the nitrite will peak. When they're both down to zero and you have some nitrates, the tank is cycled. You'll want to test daily at least during the cycling process.