When is the safest time to buy for long term?

US30 is forming a huge expanding triangle in weekly chart. I do believe that stocks are growing upward for long term for sure. However I do notice that now it’s completing a rising wedge within this huge expanding triangle. The major resistance is around 26000. For now health crisis is still uncontrolled, I think it would happen another major drop again to the support of expanding triangle then maybe a bounce from there.