Price is the single most important signal on a chart. Read price first, and then read ADX in the context of what price is doing. When any indicator is used, it should add something that price alone cannot easily tell us. For example, the best trends rise out of periods of price range consolidation. Breakouts from a range occur when there is a disagreement between the buyers and sellers on price, which tips the balance of supply and demand. Whether it is more supply than demand, or more demand than supply, it is the difference that creates price momentum.
Breakouts are not hard to spot, but they often fail to progress or end up being a trap. However, ADX tells you when breakouts are valid by showing when ADX is strong enough for price to trend after the breakout. When ADX rises from below 25 to above 25, price is strong enough to continue in the direction of the breakout.