Hi Henry,
One quick and dirty method is to use its average earnings for the past five years. Once you have the earnings, you could simply gauge the valuation based on its average earnings against the current share price. Alternatively, some analysts like to use book value as a gauge since it doesn’t fluctuate much.
Remember the valuation of cyclical companies is really depend on the future demand and supply which is highly unpredictable. Even if you could get a stock at huge discount to its net asset value and if the industry doesn;t recovered, you are likely not going to get the kind of return you’d expect.