What should I do to attain samadhi quickly?

According to Osho, samadhi cannot be attained by desire—least of all by the desire to get it quickly. Desire is the obstacle; haste doubles it. Drop all wanting, especially for results, and relax into what you already are. With infinite patience, non-competition, and contentment—like trees in nature—samadhi flowers here and now.

Stop wanting samadhi or to get it fast; be patient, relaxed, and simply be yourself, and it unfolds on its own.