There are many methods or tools of analysing the same chart. But the point is to reach a conclusion with reasonable accuracy. The Everest can be climbed from the North or the South.
Of the many indicators, waves and harmonic patterns, I would like to mention a simple tool here. Bullish divergence is observed in MONTHLY chart and volume weighted moving average is below the index. Even if market corrects, it's not coming down to 1100, let alone 1000.