Read here → 3. WD Gann Strategies - #10 by dexter
And this is Gann Square of 9 Calculator Gann Square of 9 Calculator - Unofficed
These are broad talkings. Like in Gita it said in Chapter 2 Verse 14
मात्रास्पर्शास्तु कौन्तेय शीतोष्णसुखदु: खदा: |
आगमापायिनोऽनित्यास्तांस्तितिक्षस्व भारत || 14||
Translation →
BG 2.14: O son of Kunti, the contact between the senses and the sense objects gives rise to fleeting perceptions of happiness and distress. These are non-permanent, and come and go like the winter and summer seasons. O descendent of Bharat, one must learn to tolerate them without being disturbed.
You can interpret this like this → Do not see short-term market movements. Market is cyclic and things will repeat itself like seasons.